MODERN HYDRONICS 2013 The Ins and Outs of Concrete Regs and Embedded piping systems
FEEDING THE
FLOW RATE Applying flow reversal-when, why, how
modulating
flow
effectively bringing builders on board How to select piping and control strategies for maximum comfort & efficiency Renewables in the hydronic equation a publication of
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Contents
MODERN Hydronics a supplement of Heating Plumbing Air Conditioning Magazine
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Kerry Turner (416) 510-5218 KTurner@hpacmag.com Patrick Callan
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sales & marketing coordinator
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Art Director Market Production Manager Circulation Manager PUBLISHER
Sandy MacIsaac (416) 442-5600, ext. 3242 Barb Vowles (416) 510-5103 BVowles@bizinfogroup.ca Selina Rahaman (416) 442-5600, ext. 3528 SRahaman@bizinfogroup.ca Peter Leonard (416) 510-6847 PLeonard@hpacmag.com
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4 Changing
Learn how and when to apply hydronic flow reversal.
BY JOHN SIEGENTHALER
8 Structural
Integrity Rules
A primer on concrete codes and standards for radiant system designers.
BY ROBERT BEAN
12 Getting It right
Strategies to maximize radiant system effectiveness
BY MIKE MILLER
18 The Variable
Flow Renaissance
The Pump Guy looks at the end game: modulating flow effectively.
BY STEVE THOMPSON
The Newest Member of the NTI Line Up Available in Combi Version
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26 increasing the appeal
Renewables are a more appealing pairing with new developments.
BY MARK EVANS
28 HOW TO SELL
HYDRONICS TO CANADIAN BUILDERS
An expert brings out some points you may have over looked. (From our archives)
BY AL BUSCHEL
30 capitalizing on greening
It takes more than technology to produce results.
BY STEVE GOLDIE
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MODERN HYDRONICS
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>> System Design
Changing Direction
I
spend a lot of time looking at piping schematics. Many of them show arrows next to the lines representing piping, to indicate the proper direction of flow. The “quip” about such arrows is that the installer needs to draw them on the inside of the piping as it is installed, using an indelible marker, so that the water can see them, and thus know which way to flow. Let me say that with proper design, this is not necessary.
I AM STARVING Occasionally, you may come across a hydronic system, which, for various reasons, is starved for proper flow rate. The symptoms typically include complaints of inadequate heat delivery and large temperature drops from the beginning to the end of the circuit. One example of such a situation would be a radiant floor circuit that contains 1000 feet of ½" PEX tubing. Why, you may ask, would anyone install a circuit that long? The answer is simple: Because ½" PEX tubing is sold in coils up
Figure 1 Use of a 4-way valve
to 1000-feet long. Given this, an installer with little understanding of flow dynamics, simply keeps uncoiling and fastening tubing to a floor area until the 1000-foot coil is used up. I have heard of this happening on several occasions. The realization that it is a problem usually occurs after the concrete has been placed over the tubing, thus sealing the error for posterity. I used Hydronics Design Studio software to model what would happen with a 1000-foot long circuit in a bare concrete slab, assuming the tubing was placed at 12" spacings and supplied with 105F water. I assumed a typical 1/25 horsepower circulator was used to drive flow through the tubing circuit and that the room air temperature above the slab was 70F. The results are as follows: Circuit flow rate = 0.67 gpm Temperature drop = 32.1F (supply temp. = 105F, return temp. = 72.9F) Total heat output of circuit = 10 641 Btuh Average heat output of circuit = 10.6 Btuh/ft2 Compare this to a situation where the same 1000 feet of tubing was divided up into
Figure 2 Spring return actuator
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MODERN HYDRONICS
four 250-foot long circuits. Use the same circulator and the same supply water temperature. Here are the results: Circuit flow rate = 1.26 gpm Temperature drop = 9.76F (supply temp. = 105F, return temp. = 95.2F) Total heat output of circuit = 24 449 Btuh Average heat output of circuit = 24.5 Btuh/ft2 The total heat output of the four 250-foot circuits is almost 2.5 times greater than that of the single 1000foot circuit. Furthermore, the heat output near the end of the 1000-foot circuit is a paltry 5.5 Btuh/ft2 and is very likely well under the value needed to maintain proper comfort at design load conditions. To make matters worse, it is all cast into concrete and any correction may seem impossible. It would be very expensive to tear out the slab and replace it with proper proportioned circuits. Fortunately, there is another solution that can be much less expensive and invasive. The fix is to periodically reverse the flow through the long circuits. Over time, this allows all areas of the floor to emit approximately equal amounts of heat, based on the average water temperature in the circuit. One way to do this is to use a 4-way motorized valve, one that is usually intended for mixing applications, as a “reversing valve.” The concept is shown in Figure 1. The shaft of the 4-way valve is controlled by a two-position spring return actuator, such as the one shown in Figure 2. When supplied with 24VAC, this actuator rotates the valve shaft about 90 degrees. Flow through the system would be as shown in the upper portion of Figure 1. When the 24VAC signal is removed, an internal spring causes the actuator to rotate the valve’s shaft back to its original position. Flow now moves through the system as shown in the
Photo: Bob Rohr
How flow reversal can be used in hydronic systems.
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Modern Hydronics
lower portion of Figure 1. The periodic on/off switching of the 24VAC signal to the actuator can be handled by a commonly available repeat cycle time delay relay. Although, I have not studied the effects of cycling time, I suggest setting the periodic repeat cycle to something between 30 and 60 minutes.
OTHER USES This method of periodic flow reversal can also be used in snowmelting systems. One characteristic of such systems is that snow tends to melt faster in pavement areas near the supply side of the embedded tubing circuit. This happens because the circulating fluid is warmer near the supply side of the circuit. Periodic flow reversal tends to even out the
"The realization that it is a problem usually occurs after the concrete has been placed over the tubing, thus sealing the error for posterity." amount of heat delivered by each unit of area served by the circuit. Over an operating period of several hours, this will average out the heat delivered to each square foot of pavement. If you plan to use this approach, use manifolds with either no valves, or valves that are tolerant of flow through them in either direction. Avoid globe type valves. Reversing flow through such valves, especially when the valve’s disc is close to its seat, can cause cavitation. Besides noise, this situation can eventually damage the valve’s seat and disc.
Figure 3 Maintaining stratification in thermal storage tanks
Also, be sure that there are no check valves in the piping through which flow will be reversing. Hopefully, the reason for this precaution is obvious. If not, you are probably better off not using flow reversal.
STRATIFICATION SUPERVISOR Yet another application of flow reversal is to maintain proper stratification in larger thermal storage tanks that contain heated water during heating season operation and chilled water during cooling operation. Figure 3 shows an example of such a system, which uses an air-to-water heat pump, operated
Figure 4
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MODERN HYDRONICS
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>> System Design during periods of warmer outdoor temperature, to heat a large and very well insulated thermal storage tank during the heating season. The heat pump also operates on low cost off peak electrical energy during summer nights to chill water in the storage tank. This water provides the next day’s cooling through zoned air handlers with chilled water coils. This system uses two 4-way “reversing valves,” one on the energy input side and the other on the load side. These valves operate at the same time. In heating mode, the valve on the left side of the tank provides a flow
direction that delivers the warm water from the heat pump to the top of the storage tank. The valve on the right side of the tank allows the warmest water at the top of the tank to be delivered to the load. In cooling mode both valves change the flow direction to allow chilled water from the heat pump to be delivered into the lower portion of the tank. Likewise, chilled water for the air handlers is extracted from the lower portion of the tank. Figure 4 shows a simplified concept of these operating modes. Granted, the situations and applications for hydronic flow reversal do not
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come along every day. Still, knowing how and when to apply it is another addition to your professional repertoire. Use it where it is appropriate.
- John SIEGENTHALER
John Siegenthaler, P.E., is a mechanical engineering grad uate of Renssellaer Polytech nic Institute and a licensed professional engineer. He has over 34 years experience in designing hydronic heating systems. He is also an associate professor emeritus of engineering technology at Mohawk Valley Community College in Utica, NY. This fall, Siegenthaler will be teaching an online course entitled "Mastering Hydronic System Design." Details are available at http://bnp.cammpus.com/ courses/hydronic-system-design-trainingonline.
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>> Piping
Structural Integrity Rules Understanding regulation of embedded piping systems.
W
hen it comes to hydronic piping systems, I would speculate that 99 per cent of radiant system designers are unaware that Canadian and U.S. concrete codes and standards address the placement and operation of embedded pipes. Certainly when it comes to structural concerns, hydronic codes play second fiddle to the piping pressure and temperature test and operating requirements of the concrete regulations. When working with embedded pipe systems in Canada, radiant designers should familiarize themselves with CSA A23.1, A23.2, and A23.3, respectively Concrete Materials and Methods of Construction, Test Methods and Standard Practices for Concrete and Design of Concrete Structures. For those working in the U.S., the governing document is ACI 318 Building Code Requirements for Structural Concrete. These documents address embedded pipes and are for the
Table 1 Pipe testing comparison
most part consistent in addressing test pressures, temperatures, tube spacing density, and allowable pipe diameter and tube placement/depth (see Figure 1 and Table 1). As noted in CSA A23.3, section 6.2, "Embedded pipes...shall be located so as to have negligible impact on the strength of the construction or their effects on member strength shall be considered in the design." This is not a trivial statement and although more of a concern for the structural engineer, it does not grant the radiant designer impunity from understanding the relationship between pipes and concrete.
Construction When it comes to "slab on grade" the radiant designer should be aware of the different control joint types, purpose and layout (Figure 2); insulation types and characteristics including compressive strengths1, 2; and vapour/gas barrier and placement (Figure 3). For slabs above grade, designers should be aware of consequences of tube placement (Figure 4) within the slab itself or in bonded or unbonded toppings (Figure 5).
Figure 2 Joints for slab on grade construction are inserted to control cracking and if necessary to connect slab sections. Pipes passing through or under these joints should be sleeved as per pipe manufacturer's instructions.
Figure 1 Tube placement, spacing and diameter are all regulated by concrete codes and standards. Fortunately these restrictions rarely have a negative impact on the design of radiant systems.
Figure 3 Vapour/soil gas barriers should be placed under the slab on top of the insulation.
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Modern Hydronics
Concrete and Pipe Stress Concrete consists of cement, aggregate (sand and gravel) and water. In simple terms adding water causes the cement to harden around the aggregates (Figure 6). For most slabs, stress in concrete will be due to shrinkage experienced during a typical 28 days curing cycle and will, with a few exceptions, exceed the stress caused by increases in slab temperature due to heating with embedded pipes. Thus, control joints in slabs are not there for the exclusive benefit of the radiant slab. They are also there to regulate cracking as a result of the curing process, changes in slab depths, intersections or changes in direction and changes to slab grading (slopes) (Figure 7). As it relates to pipe stresses, concrete and PEX pipe have very different co-efficients of expansion3; as such when embedded pipe, restrained by the concrete, is heated and cooled expansion/contraction stress must show up within the pipe since it is not possible for relief through pipe elongation as would be the case with uncased pipe. Due to the inward distribution of this stress over the internal structure and surface area of the pipe, any distortion would be at a microscopic level (see Table 2 and Figure 6). I won't pretend to be a "plastics engineer" but the stress is real and pipe should be engineered to accommodate
this long-term function. Beyond that I will leave the academic debate as to which method of PEX has better characteristics at handling the long-term results of internal stress relief, to the various polyethylene chemists and pipe engineers. ď‚„
Table 2 Comparison examples of expansion and contraction of concrete and PEX
Figure 6 Microscopic image of PEX-a pipe embedded in
Figure 4 FEA simulation effects of tube depth on cooling surface temperatures (4). Note the surface temperature efficacy (consistency) and back losses/gains as a result of placement. The mid position is optimal and meets concrete design and construction regulations.
concrete. Make note of the protective air barrier layers in the right-hand side image. Stress due to encased pipe being heated and cooled is absorbed internally at the molecular level.
Figure 7 Summary of control joint placement due to length and Figure 5 Typical tube placement in a hollow core structural slab with or without insulation and/or toppings.
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thickness, change of direction, change in slab thickness and grade (slope).
MODERN HYDRONICS
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>> Piping Temperature vs. strength of concrete
more
approvals
better
installations
Concrete design documentation is explicit in stating excessive concrete temperatures during the curing cycle can destroy compressive strengths (Figure 8). Under no circumstances should fluid in radiant slabs be operated at those design conditions exceeding the concrete codes and standards until the concrete has obtained its design strength. Failing to adhere to this requirement can destroy the structural integrity of the slab.
Final thoughts... When it comes specifically to structural concrete, never assume the plumbing codes and standards trump concrete codes and standards. Requirements for structural integrity will always supersede piping pressures, temperature test protocols and operating conditions. Tube depth and spacing matters; John Siegenthaler and I have discussed the effects on back losses, operating temperatures and thus plant efficiency and surface temperature efficacy. Keep the tubes within the recommended depth of the concrete codes and standards — for all but special applications the tubes are best located in the upper portion of the slab. Embedded pipes are permanent and affect system efficiency. Use only the highest quality product available and use lots of it to guarantee the lowest temperatures in heating and highest temperatures in cooling. For slab on grade construction ensure those responsible for the placement of the slab have considered the proper layout and construction of control joints and
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Figure 8 Relationship of concrete strength to curing temperature. Image adapted from Design and Control of Concrete Mixtures, Portland Cement Association, 2003
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"Certainly when it comes to structural concerns, hydronic codes play second fiddle to the piping pressure and temperature test and operating requirements of the concrete regulations." safeguard any pipes passing under or through the joint following manufacturers procedures. When selecting rigid insulation make certain the compressive strength is suitable for the application. I know of one manufacturer that offers loading analysis for special applications such as heavy equipment rolling across slabs in industrial buildings. Vapour and soil gas barriers should be placed under the slab and on top of the insulation. This mitigates damage to the barrier and prevents slab moisture from accumulating within the insulation. For slabs placed on soils bearing on high water tables use low water absorption and low vapour permeance insulations such as Type 4 extruded polystyrene board stock. As Master Po would say to the young Grasshopper, do this and you will have alleviated the most common issues with embedded pipes in concrete. - robert bean Robert Bean, R.E.T., P.L.(Eng.) is president of Indoor Climate Consultants Inc. and a director of www.healthy heating.com. He serves on ASHRAE Committees: T.C.61. (CM), T.C.6.5 (VM), T.C. 7.04 (VM), SSPC 55 (VM). www. healthyheating.com 1
Bean, R., Pay Now or Pay Later: Modelling downward heat losses - a last opportunity before a lost opportunity, Heating Plumbing Air Conditioning Magazine, March 2011
2
Bean, R., All Points Bulletin, Plan reviews and field inspections: Under slab insulation (redux), Heating Plumbing Air Conditioning Magazine, November/December 2011
3
PEX co-efficient of expansion is appx. 1" (25mm) every 100' (30.5m) of tubing for every 10째F (5.6째C) of temperature change. For co-efficient of expansion of concrete using various aggregates see, Design and Control of Concrete Mixtures, Portland Cement Association, 2003
4
Bean, R., The Fundamentals of Radiant Cooling System Design and Construction, Radiant Slabs On-Site Fabricated Heat Exchangers, ASHRAE Denver 2013, Seminar 38
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MODERN HYDRONICS
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>> Piping & Controls
Getting It Right Strategies to maximize radiant system effectiveness.
T
his review of mechanical piping and radiant loop layouts and their differences, as well as control strategies, will help you on the road to designing top-notch systems in terms of performance, efficiency and cost.
Piping of Mixing Devices When working on a single water temperature boiler system, the mechanical piping arrangement is quite simple and the load can be piped right off the boiler. However, many boiler systems today consist of a high temperature load such as DHW and fan coils, as well as a low temperature load such as radiant. In that case, most commonly, some form of mixing device is installed. This allows for simultaneous operation of loads with different water temperature requirements and improves efficiencies. Mixing device options include: two-way injection valves*; three-way or four-way mixing valves; or, variable speed pump injection systems. Three- and four-way mixing valves are more common than the two-way and should be modulated with either a floating (24 or 110Vac) or modulating (0-10Vdc) signal to provide an outdoor reset water temperature to the radiant system. When the piping configuration of those mixing devices is implemented improperly the system performance can be compromised. Figure 1 and Figure 2 show two piping configurations with flow in the boiler loop, but the primary pump and heat source, as well as any high temperature loads, are omitted for clarity. It is assumed that all high temperature loads are taken off and a primary pump is installed prior to the mixing device. The same is true for the remaining Figures. Figure 1 shows how 3- or 4-way mixing valves are frequently installed. In these two examples, there is no hydraulic separation between the primary 12 | september 2013
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pump and the radiant pump and once the mixing valve is fully open, two pumps work in series effectively, changing the system flow considerably. This can lead to velocity noises on the radiant side, but also to increased strain on
the system components, particularly the motorized mixing valves. Figure 2 shows the proper installation of a mixing device off the primary loop. Two closely-spaced Tees allow for hydraulic isolation of the primary loop and
Figure 1 Improper installation of a mixing valve
Figure 2 Proper installation of a mixing device
MODERN HYDRONICS
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Modern Hydronics
the secondary/radiant loop, effectively isolating the two pumps from working in series. To attain effective isolation a few basic guidelines must be followed. Those are shown in Figure 3, where: A = MIN 6 x diameter of primary loop pipe size; and B = MAX 4 x diameter of primary loop pipe size.
Figure 3 Proper Hydraulic Separation
Table 1 Pipe Sizing (@20F delta T) Tubing
Copper
GPM
Pipe Size (in.)
20-40K
2-4
3/4"
40-90K
4-9
1"
BTU/h
60-160K
6-16
1-1/4"
100-210K
10-21
1-1/2"
200-450K
20-45
2"
Pipe Sizing (@10F delta T) Tubing
BTU/h
GPM
Pipe Size (in.)
10-20K
2-4
3/4"
20-45K
4-9
1"
30-80K
6-16
1-1/4"
50-105K
10-21
1-1/2"
100-225K
20-45
2"
Copper
Pay close attention to A and B, as references are sometimes in inches for each that do not align with the actual requirement. Note: Mixing Valves need to be sized based on flow requirements, not to the pipe size of the main loops. For example: a 100 000 Btuh radiant system operating off a 10F ΔT requires 20 GPM flow (Flow = Btuh/(ΔT x 500)). The system piping, if in copper, would be 1-1/2" according to Table 1, where the mixing valve would only need to be at 1-1/4", according to Table 2 (see CV Value). Another common mixing device is the variable speed pump injection system. Here, the speed of a pump is controlled by controllers, which change the frequency and the voltage supplied to the pump. This modulates the amount of heat transfer between the boiler/primary loop and the secondary/radiant loop to attain water temperature control. The piping requirements are similar to those of the mixing valves. A and B remain the same for variable speed injection systems as shown in Figure 4. Additional requirements include: C = MIN of 12" drop (creates a thermal trap, which prevents convective heat transfer) D = MIN of one pipe diameter smaller than the secondary/radiant loop E = Balancing or Globe valve for flow balancing Since most pumps on the market today vary with output based on head
pressure and a balancing valve is installed on the injection loop's return, fine-tuning of the output is easily attainable while the controls output is at 100 per cent. In my experience, the simple Flow = Btuh/(ΔT x 500) formula gets me into the ballpark, with the exception that in this example, the ΔT is the temperature difference of primary loop supply and secondary/radiant loop return. For example: Injection Flow = 100 000 Btuh / ((180F-110F) x 500) = 2.85 GPM Sizing an injection pump exactly requires you to have the following, along with the Injection Flow Ratio Chart in Figure 5: • Primary/Boiler Loop Supply Temp. (Tb) • Secondary/Radiant Supply Temp. (Ts) • Secondary/Radiant System ΔT (ΔTs) • Seconday/Radiant System Flow Rate (SF) Using the chart in Figure 5, identify the Flow Ratio (FR) in GPM using 180F (Tb) – 120F (Ts) and 10F (ΔTs). In this example, that would be roughly 0.14 GPM. Now, take your 20 GPM SF x 0.14 GPM flow ratio (FR) = 2.8 GPM design injection flow rate. Pick the best wet rotor circulator that can give you that flow and use the balancing valve on the injection loop return to adjust the heat pressure to suit.
CONTROL STRATEGIES Water temperature control is essential when working with radiant floor heating systems. Without it, the system efficiency and performance would be greatly
Figure 4 A and B in variable speed injection systems
Table 2 Mixing Values Pipe Size
CV Value
3/4"
7
1"
14
1-1/4"
21
1-1/2"
32
2"
51
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MODERN HYDRONICS
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>> Piping & Controls compromised when the heat loss of a building is reduced due to a milder outdoor climate. Figure 6 pictures the differences within space temperature control using a standard thermostat with a 1F on/off differential when compared to no outdoor reset during reduced building heat loss on the top, with outdoor reset in the middle and finally, outdoor reset with indoor temperature feedback on the bottom. No outdoor reset water temperature control – even though the thermostats turns ON 0.5F below room setpoint, the floor does not immediately put out heat into a space until the heated water is circulated for a while and the mass of the slab warms up. That timed delay can cause the space temperature to continue to fall until then. At the same time, when the thermostat turns OFF 0.5F above room setpoint, the floor now continues to put out heat into the space even though the heat- 
Figure 5 Flow Ratio Chart
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>> Piping & Controls Formula 1 Calculating heating curve
ed water circulation has stopped while the mass of the slab cools down. This will often result in temperature swings of greater than three to four degrees Fahrenheit during milder outdoor temperatures, since the water temperature, traditionally set for the worst case scenario (coldest day of the year), is fixed. With outdoor reset water temperature control – having the water temperature now regulated based on outdoor temperature and in coordination to address changing heat losses of the building, that same thermostat now seemingly performs better. That is mainly due to the fact that its ON and OFF times are now greater and the heat input versus output to this space is more dynamically controlled with water temperature. Outdoor reset water temperature control can get very close to the actual requirements of a building, but cannot consider internal heat gains and additional losses. Nevertheless, outdoor reset alone should be the absolute bare
minimum on any radiant system. Outdoor reset with indoor temperature feedback - Adding indoor temperature feedback to outdoor reset provides even greater accuracy to radiant space temperature control. In this case, a traditional thermostat would be replaced with a sensor or communicating thermostat where it provides internal heat gains and additional losses to a reset water temperature controller, resulting in constant delivery of just the right water temperature to the space. Here, the comfort level is typically maintained with an accuracy of 0.5F. The user interface and configuration of outdoor reset controllers/devices has become straightforward and manageable for virtually anyone, providing the knowledge of the input requirement is there. Most modern digital controllers require you to input the following three pieces of information in order to setup a heating curve: esign Outdoor Temperature (Dsgn •D
Outdoor) which is the coldest outdoor temperature the building's heat loss is being designed to (e.g., 10F) • Design Indoor Temperature (Dsgn Indoor) which is the desired Indoor Temperature the building has been designed for on the coldest day of the year (e.g., 70F) • Design Supply Water Temperature (Dsgn Sup) which is the water temperature required on the coldest day of the year to heat the building to the desired indoor temperature (e.g., 120F) For non-display controllers/devices, a heating curve/ratio needs to be calculated, as shown in Formula 1. Contractors who are committed to achieving maximum efficiency and comfort for their clients must understand the ins and outs of radiant system piping strategies, system components and controls. A healthy dose of the keep it simple principle does not hurt either. - Mike Miller Mike Miller is national business development manager with Uponor Canada Ltd. Contact him at mike.miller@ uponor.com. *I very rarely see 2-way injection valves, which is why they are excluded from this article.
Look to Runtal for INSPIRED RADIANT heating solutions. Comfort, style, durability, versatility and ENERGY EFFICIENCY are the hallmarks of residential and commercial building spaces designed the Runtal way. The worldwide LEADER in standard and custom designed radiators for over 50 YEARS our ENGINEERING ASSISTANCE takes the guess work out of every job. And when it comes to off-the-shelf solutions, you can rely on our IN-STOCK solutions.
1-888-829-4901 www.runtalradiators.com 16 | september 2013
MH2013_12-17_Miller2.indd 16
MODERN HYDRONICS
www.hpacmag.com
13-08-28 10:09 AM
"We’re going to change the way you think about water heating ." – Dave Davis, CEO & Owner
316 L Stainless Steel Tanks
Phoenix Light Duty 95% Eff iciency • 76K Btuh
Ever l ast Electric 10 Year Commerc ial Warrant y Lifetime Residential Warrant y
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13-08-28 10:09 AM
>> Pumps
The Variable Flow Renaissance The Pump Guy looks at the end game: modulating flow effectively.
O
ver the last half decade plus there have been a number of pump manufacturers getting into the variable flow market here in North America. End-users, maintenance technicians, wholesalers and installers have to sift through: the various features and benefits; the reasons for installing variable flow versus not; and the when and where questions this variable flow renaissance has brought about.
able flow circulating pump. The big question is: What is the best way to control (∆T, ∆P, Auto or External) the system. ∆P is nice as it does not require the installation of external sensors but this does not work in some applications such as boiler protection, zoning circulators and injection. ∆T or set point temperature works in all applications but requires sensor(s). If you are in doubt ask a trusted expert.
What is variable flow?
Circulator or Pump
Simply put, variable flow means “changing” flow, but becomes a more complicated concept depending on how, why and when the change is done. Most of the time this is accomplished with a circulating pump that changes speed depending on what the system or application requires. However, you could affect flow change by using a modulating two-way or three-way valve, but that is a topic for another day. The following six basic concepts will help with the decision making process.
Pumps consume or convert energy to boost pressure – for example a submersible well pump or a boiler feed pump. The application requires pressure boosting. Circulators consume or convert energy to create flow by overcoming piping and fitting friction losses caused by the flow itself. The application requires flow. Hydronic HVAC systems require flow to distribute heating or cooling (Btus) throughout the building. Higher loads require higher flows (more pounds of Btu carrying water) and higher flows increase friction losses.
1
System Curves versus Constant Speed Pump Curves
Static or Dynamic Applications Variable flow products are best suited for dynamic applications. These are applications where the flow is required to change, as opposed to static systems where flows are constant. Hydronic heating or cooling systems are 99.9 per cent dynamic. Flows change as heating or cooling loads change, a function of the laws of thermodynamics (Btus are affected by ∆T and circulated pounds of water or US GPM). I have been questioned about two applications that might not be dynamic – boiler primary and individual pumped zones.
Boiler Primary
2
The piping system that moves Btus from the boiler(s) between the boiler loop supply and return would only be a static, constant flow application if there was only one on/off boiler on this loop. If there was one boiler with a modulating gas valve, to maintain a specific ∆T or to control the return water temperature, the flow would have to be modulated with the firing rate of the boiler – hence this is a dynamic, variable flow application.
3
Individual Pumped Zones This is also know as zoning with circulators. Indeed, if this single zone did not see any load change it would be static. However, as the room temperature is satisfied wouldn’t it make sense to slow the circulator down and modulate its flow based on room load? This makes it dynamic. So, it is safe to say all hydronic HVAC applications would see a system efficiency benefit by using a vari18 | september 2013
MH2013_18-20_Thompson.indd 18
4
Both curve types have head on the “Y” or vertical axis and flow on the “X” or horizontal axis. Flow could be expressed in GPM or Btus (think about it). The System Curve is a graphical representation showing the effects of changes in flow and subsequent changes in friction loss (more flow=more friction). This curve starts at “0/0” (zero flow means zero friction loss) and head loss increases as flow increases. Constant speed pump curves have two distinct points on this graph. The differential head at zero flow is shut off head or the highest head this constant speed circulator can produce. All of the 80 watts of power this little guy is using is going into producing head. The other is maximum flow (run out) where the differential head is the lowest (or even zero).
5
Common Misconceptions: •B alancing is not required when variable flow pumps are used. This is not true, balancing is still required – but less of it. • Bypass circuits or wild loops are not required with variable flow pumps. It actually depends on how low the flow would be reduced and the minimum flow required by the boiler (or chiller). • All boilers can benefit from dedicated variable flow “shunt” pumps. Be careful with this. Unless the circulator can communicate directly with the system (either 0-10Vdc from the boiler or ∆T), having a boiler and pump with separate brains is not a good idea.
MODERN HYDRONICS
www.hpacmag.com
13-08-28 10:11 AM
Modern Hydronics
Let’s state the obvious: • A circulator provides flow by overcoming friction loss in a closed loop application. • A constant speed circulator increases head as flow decreases. • Friction head decreases as flow (or load) decreases. • As zones close (loads go down), Btus (flow) required goes down as does friction loss, but the constant speed circulator’s differential pressure on the pump curve goes up. This is bad and causes a loss of system efficiency (boiler cycling and low ∆T) and loss of overall comfort (noise and poor room temperature control in shoulder heating seasons). So, if you have ever wondered why some zones are noisy than others, what causes zone valves to fail prematurely, what causes boilers to cycle it is a misapplication (or oversizing) of a constant speed circulator. The circulator really needs to lower its differential head during decreases in flow, as in the case of a WORTH NOTING: Closed loop three-storey buildings do not require circulators sized with an extra 30' of head (10' per floor) since the loss going up is gained coming down. Size the circulator to provide flow to satisfy the coldest day and the highest friction loss at that flow.
6
∆T circ. As an analogy, the more closed a shower valve is the more noise it makes.
Closed Loop or Open Loop:
Closed loop systems are typical of hydronic HVAC systems where the closed and pressurized system requires thermal expansion tanks. They have very low or no system make-up system fluid. Open systems (cooling towers, domestic or sanitary water) are classified as open systems. These are typically high or 100 per cent make up water and quite often have an open discharge. This is important when selecting pumps – materials of construction, high or low head, flat or steep curves and so on. In summary, do not overthink the variable flow stuff – it is really very simple. All circulating pumps have a goes inta, a goes outta and one moving part (impeller). The end game is to modulate flow with system demand for maximum system efficiency and comfort – like controlling the speed of your car with a gas pedal. - Steve Thompson Steve Thompson, is director of residential product management with Taco Inc.
PEOPLE. SOLUTIONS. VALUE. Industry leading service. It’s what we do. With 20,000 parts stocked on the warehouse floor, an in-house training facility to teach your installers the best techniques on the latest systems, and engineering support with deep experience in hydronics—we have what you need. We can even find the manual for you. Because it’s our business to support yours.
Call us at 1-866-594-0767
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MODERN HYDRONICS
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September 2013
| 19
2322_AQ February 10, 2012 13-08-28 10:11 AM
>> Products Aquatherm’s North American Installer Manual fits into an installer’s pocket or tool case and includes colour pictures along with step-by-step instructions. It is oriented so that it is easy to prop open for viewing while working. The manual is intended for use with the Aquatherm Installer, Butt Welding and Electrofusion courses. www.aquatherm.com
Compass circulators from Armstrong offer a broad operating range, producing up to 20' of head and 20 US GPM flow. Features include: Design Envelope technology to simplify circulator sizing and Viega ProRadiant mats allow the in-
White-Rodgers’ universal nitride ignitor
selection; efficient motor technology and intelligent
stallation of large amounts of tubing
replacement, HotRod Universal Hot
variable speed operation; a front mounted terminal
quickly for commercial radiant heating
Surface Ignitor, is packaged for con-
block reduces installation time; and the compass
and cooling applications. The mats are
tractors in a single pack as 21D64-2
“auto” algorithm adapts to system demand.
pre-engineered, pre-assembled and pre-
and in a truck stock five-pack carton as
www.armstrongpumps.com
pressurized with temporary test headers
21D64-5PK. The 21D64-2 is the same
and slab penetration sleeves. They are
replacement ignitor that contractors
available in a range of lengths in 6-in.,
use to replace silicon carbide ignitors
9-in. and 12-in. on-centre spacing and
in gas-fired forced-air furnaces, water
are suited for use in large open areas
heaters and boilers – now replacing
such as warehouses, garages, manufac-
over 150 different ignitors. The sim-
turing plants, schools and airport termi-
plified design of the mounting bracket
nals. www.viega.com
simplifies installation across a range of equipment and applications. www. wrhotrod.com
Axiom’s brass and stainless steel hydronic sideThe Rinnai Q Series offers a fully modulating
stream filter package delivers ongoing protection
pump coupled with a proprietary stainless-
against the damaging effects of debris in all types
steel heat exchanger to make this one of the
of heating and cooling systems. FilterPak features a
more efficient units available. With BTU inputs
double O-ring on the filter housing, two glass windows
ranging from 85 000 to 205 000, the Q Series
and a manual balance valve, which provides flow me-
is ideal for any home or light-commercial appli-
tering, flow balancing with memory stop and filter car-
cations. The Q Series is approved for venting
tridge isolation. An integral manual air vent prevents
lengths up to 200 ft. and complies with low NOx
the introduction of air during cartridge change. A ball
requirements.
valve drain with hose connection and cap ensures
www.rinnai.us
safe fluid handling. It comes with a DOE 25 micron cotton wound filter cartridge. Two glass windows offer improved fluid visibility. www.axiomind.com
20 | september 2013
MH2013_22-25_Products.indd 20
MODERN HYDRONICS
www.hpacmag.com
13-08-28 10:12 AM
Viega ManaBloc® Simplicity providing extraordinary performance The Viega ManaBloc is a unique innovation that offers a dedicated distribution line to each fixture in a plumbing system. Viega ManaBloc system users enjoy faster hot water delivery than a branch and main plumbing system, which not only increases energy savings but limits wasted water throughout the year. Viega ManaBloc features and benefits • Complete control of the plumbing system from a central location • 1¼" reservoir helps maintain pressure balance during multiple fixture use • PLS plastic (polysulfone) resists aggressive water and corrosion • Quick and efficient installation • Reduced wait time for hot water • Reduced water waste • Qualifies for LEED points • Compatible with all Viega PEX connections • Comprehensive 10-year warranty
www.viega.com | 1-800-976-9819
Viega ManaBloc Designed for dramatic water and energy savings The global leader in plumbing, heating and pipe joining systems
MH2013_22-25_Products.indd 21
13-08-28 11:46 AM
>> Products PolyPro venting system from Duravent is tested and listed to the ULC S636 standard. It is recyclable and does not contain toxic or carcinogenic materials, chlorides, or heavy metals. www.duravent.com
Thermo 2000’s Combomax Ultra 12 sup-
gas water heater for commercial applica-
plies hot water to hydronic heating and
tions is built with 316L stainless steel ma-
potable water systems in residential appli-
terials. The Phoenix LD operates at 95 per
cations of up to 2000 ft2. It has an intermit-
cent thermal efficiency and offers multiple
tent capacity of up to 12 gallons/minute
installation options. It also features an
and features adjustable temperature from
easy to program LCD display.
30C to 60C. Capacities are available from
www.htproducts.com
three to 12 kw. www.thermo2000.com
7
2
2
HTP's Phoenix Light Duty (LD) condensing
oo
th
#
1
Custom Control Panels
M
Ex
po
B
Communication Gateways
P
Pump Modules Printed Circuit Boards BMS Integration ik
Versatron
DESIGN
QUALITY
KWE Technologies Group
With over 25 years of controls experience the KWE Technologies Group team will work with you from design to startup while ensuring all your requirements are fulfilled.
A Subsidiary of K-W Electronic Service Inc.
750 McMurray Road Waterloo, ON N2V 2G5 T: 519.747.5042 F: 519.747.4448 www.kwe-tech.com sales@kwe-tech.com 22 | september 2013
MH2013_22-25_Products.indd 22
SUPPORT Uponor’s Radiant Ready 30E includes a 30 000-Btuh electric boiler, an engineered plastic (EP) heating manifold, pump, expansion tank, pressure-relief valve, isolation valves, thermostat and air vent preassembled and pre-wired into one unit. The installer hangs the panel on a wall and connects the tubing, thermostat and electrical power. It is designed to cover up to 2000 sq. ft. of radiant floor heating (based on 15 Btuh/sq. ft.) and 4000 sq. ft. of radiant floor warming (based on 7.5 Btuh/sq. ft.). It comes standard with a five-loop manifold, which can be customized to add additional loops if necessary. www.uponor.ca
Versatro
nik
MODERN HYDRONICS
www.hpacmag.com
13-08-28 10:12 AM
Modern Hydronics
PolyPro ®
The tekmarNet thermostat 553 is a communicating thermostat designed to operate two heating stages, one cooling stage, a fan and relative humidity. The heating stages can be hydronic, forced air or a single-stage heat pump. The cooling stage is either an air conditioner or heat pump. There are two auxiliary sensor inputs available to measure room, floor, outdoor, coil or duct temperature. The optional floor sensor allows precise heating of radiant floors by controlling the floor temperature and maintaining the desired room air temperature. Relative humidity levels can be measured and controlled using the built-in humidity
Venting For High-Efficiency Condensing Appliances Fast
Lightweight and designed for quick and easy assembly.
Safe
No sharp metal edges.
Clean
No corrosion of metals or chlorides. No messy solvents or glues.
sensor. www.tekmarcontrols.com
Sustainable
Corrosive condensate resistant and 100% recyclable.
Listed System
See our appliance approval list online.
Designed for residential space heating and domestic hot water production, the gas-fired Greenstar boiler line from Bosch Thermotechnology offers high thermal efficiency condensing (up to 98.7 per cent). Greenstar models are available in configurations ranging from 57.2 MBH to 151.6 MBH. Two new models will be introduced this fall – the Greenstar Space Heating 79 and the Greenstar Combi 131 – featuring a concentric venting system and a twin-pipe polypropylene venting system. www.boschheatingandcooling.com/Greenstar
800-835-4429 www.duravent.com © 2013 www.hpacmag.com
MH2013_22-25_Products.indd 23
MODERN HYDRONICS
september 2013
| 23
13-08-28 10:13 AM
>> Products Belimo has released a new three-way ball
Stiebel Eltron’s Accelera 300’s
valve to replace its three-way VS ball valve
compressor and fan consume
for ½ in. to 2 in. [DN 15 - DN50]. The L series
1 kWh of electricity to gener-
ball valve meets application requirements for
ate the heat equivalent of 3
dual temperature hydronic systems where a
to 5 kWh. The E nergy Star
single valve serves both heating and cool-
rated heat pump water heater
ing loads. The media temperature range is
offers an 80 gallon capacity,
-10C to 120C and the flow coefficient values
a 2.51 energy factor, 2.2 kW
are slightly greater for the L series ball valve
(including backup) power input
compared to the VS ball valve. The L series
and 1739 kWh/year power
ball valve is motorized with standard Belimo
consumption.
direct couple actuators. www.belimo.com
www.stiebel-eltron-usa.com
The AB-QM pressure independent control valve from Danfoss combines balancing RBI’s Futera Fusion high efficiency water
and control for improved system perfor-
heaters and boiler units are designed for
mance and lower installation costs. With a
Slant/Fin’s Lynx 150 modulating gas boil-
applications of up to four million Btus
dynamic differential pressure regulator and
ers operate at 95 per cent AFUE and are
with low operating, return, or make-up wa-
a temperature control valve, it is designed
available in three sizes. They feature an
ter temperatures. The full modulation fir-
to reduce energy costs when applied on a
advanced design long-life cast aluminum
ing system continuously varies the energy
variable flow HVAC system. It is “plug and
heat exchanger and all boilers are ready for
input to match heating load to provide
play” ready for quick setup for balancing and
floor standing or wall mount. Other features
high part-load efficiencies. PVC vent ap-
its compact design allows for installation in
include natural or LP gas, PVC/CPVC vent
proved, the condensing secondary heat
areas with limited space. www.abqm.us
pipe up to 100 ft. equivalent length, all con-
exchanger is solid stainless steel. It oper-
nections are on the top, easy access termi-
ates in full condensing mode at all times,
nal strip for wiring and quiet operation. Lynx
while a temperature mixing system pro-
150 are suited to radiant, baseboard, DHW,
tects the boiler’s primary heat exchanger.
Idealzone
or mixed applications. www.slantfin.ca
www.rbiwaterheaters.com
assembled mani-
pre-
fold kits from Bow Plumbing
Group
Allied Engineering has released the HSE condensing
include end sup-
boiler with a dual copper waterway heat exchanger. The
ply manifolds, end
unit combines central heating and domestic hot water in
return manifolds, ball valves with thermome-
a single compact appliance that is available in 145 MBH
ter and self-sealing end pieces. The number
and 125 MBH sizes.
of ports may be specified and the kits are
www.alliedboilers.com
available in 1 in. and 1-1/4 in. sizes. www.bow-group.com
24 | september 2013
MH2013_22-25_Products.indd 24
MODERN HYDRONICS
www.hpacmag.com
13-08-28 10:13 AM
v
IMPROVE PERFORMANCE IN FOUR WAYS
MULTI-FUNCTION ™ 5495 SERIES MULTI-FUNCTION SEPARATOR Combines four different functional components into one separator. 1) Hydraulic Separation 2) Air Separation 3) Dirt Separation 4) Magnetic Separation of ferrous particles
Watch our videos on
www.caleffi.us
MH2013_22-25_Products.indd 25
13-08-28 10:13 AM
>> Renewables
Increasing The Appeal More options are emerging for pairing hydronics and renewables.
T
he saying “What’s old is new again” is certainly valid when it comes to hydronics. That is because we have adapted old technology, improved it and found new applications for it. The efficiency of these evolved systems has improved. In fact our focus has been on efficiency, the buzzword in our industry. “Hydronic systems offer up to 30 per cent better efficiency than air systems.” Does this sound familiar? How has that increased efficiency manifested itself? Combustion efficiency was the focus when I entered the industry and since then we have progressed from single-pass atmospherically vented boilers being the norm to them now being the exception. Consumer demand and government regulation have both driven change here and compelled manufacturers to improve to the point where condensing boilers are reliable products that deliver good value. However, I also believe that we have reached the point of diminishing return. This is the concept that states “Once a commodity reaches a yield rate that after a certain point fails to increase proportionately to additional outlays, such as outlays of capital or investments of time and labour, it has reached its point of diminishing return.” Why would a manufacturer invest millions of dollars to develop boiler technology that could increase combustion efficiency by one or two per cent and just as importantly, would anyone want to pay the price for this technology? We later recognized the need to improve piping, control and overall distribution system efficiencies. We stopped piping wild loops in baseboard systems, near boiler piping methods evolved and we improved mixing methods. But we may be near the end of this cycle of improvements. The latest innovation, the introduction of ECM motor pumps, controlling Delta P, Delta T, and being able to achieve variable flow/pressure outputs as a result, are now common ways to reduce electrical consumption.
Change in Focus It is great that we have improved the combustion efficiency and distribution efficiency of systems, but has our focus been too narrow? As an example, the installation of solar thermal for domestic hot water pre-heat requires the integration of storage of offpeak period production for peak period use. How do we move beyond the paradigm of specific applications to more fully embrace renewable energy? One answer lies in a concept I will call Intergration. The barriers to fully realizing the potential of renewable energy exist both at the point of production, as well as at the point of consumption. Much of this can be attributed to the fact that problems and solutions exist in exclusion of one another at the level of the producer and 26 | september 2013
MH2013_26-27_Evans.indd 26
the consumer. Intergration brings together point-of-use and point of production issues such as: energy storage; peak use demand; threshold, stepped or tiered energy pricing models; and relative costs of various heating fuels per Therm. The solution lies in integrating the point of use and the point of production. Hydronics, and specifically low temperature radiant, presents a platform, which easily Intergrate the benefits of renewable energy sources. Starting with energy storage, let’s look at some recent developments that offer potential solutions. Electrolyzer devices — Two University of Calgary researchers have discovered a way to make affordable and efficient catalysts (called electrocatalysts) for converting electricity into chemical energy. Having cheap and efficient electrocatalysts would enable homeowners and energy companies to store and reuse, whenever needed, intermittently generated electricity such as solar and wind power. The research has been published in http://www.sciencemag.org/ and the researchers have formed a spin-off company, FireWater Fuel Corp., to commercialize the electrocatalysts for use in electrolyzers. The company expects to have a commercial product in the current large-scale electrolyzer market in 2014, and a prototype electrolyzer, using the new catalysts, ready by 2015 for testing in a home. Electrolyzer devices use catalysts to drive a chemical reaction that converts electricity into chemical energy by splitting water into hydrogen and oxygen fuels. These fuels can then be stored and re-converted to electricity for use when it is needed. The only byproduct from the energy system is water, which can be recycled through the system. To store and provide renewable power to a typical house would require an electrolyzer about the size of a beer fridge, containing a few litres of water and converting hydrogen to electricity with virtually no emissions, the researchers say. According to UToday, the key to their discovery is that they deviated from conventional thinking about catalysts, which typically are made from rare, expensive and toxic metals in a crystalline structure. Instead, the researchers relied on simpler production methods using abundant metal compounds or oxides to create mixed metal oxide catalysts. Solar cooling — In regard to peak use demand, air conditioning is responsible for six per cent of total energy consumption in the U.S., according to the U.S. Energy Information Administration’s (EIA) most recent Residential Energy Consumption Survey (RECS). It is coincidental that peak use hours for air conditioning correspond to the higher levels in the Stepped or Tiered energy pricing models of electric utilities. The Energy Resource Center in Downey, CA, is operated by Southern California Gas and serves as a showcase for new solar cooling technologies. According to the
MODERN HYDRONICS
www.hpacmag.com
13-08-28 10:14 AM
Modern Hydronics
project brief: In early 2008, Southern California Gas Company grid.” Panasonic continues as a market leader in Japan, recently (SoCalGas) launched a showcase pilot demonstration project for having released a second generation of residential fuel cell proda solar thermal hot water system that could provide chilled water, ucts. According to the company, “The "Ene-Farm" fuel cell co-genhot water and electricity for SoCalGas Energy Resource Center eration systems generate electricity through a chemical reaction (ERC) in Downey, CA. The system uses water heated by the sun to between oxygen in the atmosphere and hydrogen extracted from provide the energy needed. It can simultaneously provide chilled city gas. The heat generated as a byproduct of this process is also water for space cooling from a hot water-activated absorption used for hot water supply. This system is extremely eco-friendly. chiller and hot water for either domestic use or space heating. It Since the electricity is generated and used at the same place, there consists of two types of concentrated solar collectors that proare no losses in transmission. Also, all heat produced during elecduce hot water. One is a parabolic trough and the other uses Frestricity generation can be used without waste. Compared to connel lenses and incorporates concentrated photovoltaics to proventional method of using electricity from thermal power plant duce electricity in a cogeneration configuration. Both collector and hot water supply using city gas, the fuel cell system allows pritypes track the sun on a single axis automatically. The electricity mary energy consumption to be reduced by approximately 37% produced is delivered directly to the electrical distribution system and CO2 emissions by approximately 49%.” of the building while the hot water produced is stored in a hot The relative cost of energy as measured by cost per therm has water storage tank. The storage tank is connected to a high-effilong influenced system choices for heating and cooling. An interciency back-up hot water heater so that the system can be operesting tool is available on the Penn State web site*, which allows you to compare what your own local costs would be based on the ated in the absence of sunlight. The storage tank also serves as a fuel options and costs in your market. I compared the cost of elecdistribution point for the hot water to be used for DHW, space tricity versus natural gas for a consumer in BC and the result is heating and/or cooling. When in cooling mode, hot water is shown in Figure 1. pumped to an absorption chiller that generates 10 tons of chilled Hence, it is understandable that most homes are heated by water as a base load for the building’s air conditioning system. natural gas, but why are most cooled with electric heat pumps Night sky radiant cooling — The Carnegie Institution for Scior air conditioning systems? According to gasairconditioning. enceCenter for Global Ecology building is an example of a project org “Natural gas cooling helps reduce demand charges, frees that utilizes night sky radiant cooling. According to the project proconsumers from higher summerfile, “During summer nights, water time electric rates for cooling, and sprayed over the roof loses heat to Figure 1 Fuel cost comparison the cold night sky. The cooled water improves the reliability of the is collected and stored in an insulatelectric grid.” ed 12,000-gallon tank and pumped As an industry we seem to have through the building during the day. these fuel biases that are based on This system supplies chilled water at what our primary need is. If we look 55-60 degrees F for an energy cost of at the totality of the system would 0.04 kW/ton and a water usage one we make different choices? If our half of that of conventional water systems are designed to anticipate cooled systems.” The Western Coolthe problems of energy storage, ing Efficiency Center at UC Davis has peak use demand leveling, tiered also done research on this technoloenergy pricing, and economy based gy as part of their study of thermal on fuel costs could we apply the exstorage options. pertise that we have developed in Fuel cells — At the June 2013 Hydrogen + Fuel Cells 2013 Interour pursuit of the old efficiencies (combustion and distribution) national Conference and Exhibition in Vancouver, BC, it was anto the integration of renewables and offer a new type of "system" nounced that “As part of its beneficiation strategy and the drive to efficiency? Food for thought and proof that “what is old is new improve on the uses of platinum, the South African Government, again.” through its funding institutions, will partner with Ballard Power Systems and Anglo American Platinum with initial field trials of a During the course of his career in the mechanical industry Mark Evans has worked in the wholesaler and manufacnew methanol-fuelled ‘home generator’ prototype product deturer sectors in sales and marketing positions. Contact signed for use in off-grid residential applications. The product enhim at mark@markevans.net. compasses a complete fuel cell system, including fuel cell stack, methanol fuel processor and other components needed to meet *http://extension.psu.edu/natural-resources/energy/energy-use/ the market requirements of rural electrification within a local minimaking-decisions/comparison-charts www.hpacmag.com
MH2013_26-27_Evans.indd 27
MODERN HYDRONICS
September 2013
| 27
13-08-28 10:14 AM
>> Looking Back - circa 1964
How to sell hydronics to Canadian builders An expert brings out some points you may have overlooked. By Al Buschel
I
the builder knew how hydronics could help him sell more profn this industry most of us sit around saying we can’t sell itably he would be willing to buy it. the builder on hydronics because the price is too high. At any rate, the contractor who sits around lamenting his Well, the fact is that you don’t sell builders on anything— high price and calling the builder cheap will get no place. they buy it! And there is a big difference between selling For those of you who are interested in getting into profitsomething and getting someone to buy something. The fact is able hydronics by learning how to make the builder buy there we haven’t convinced Mr. Builder to buy our heating system. are a number of approaches that work. I think, though, that Yet he’s buying fancy glass and chrome wall ovens. And he’s it’s important to restate what was said before about the conpaying more than he should for a stove. tractor improving his technical knowledge. Also his ability to Now, all of these items cost more, and none of them are as install more rapidly through the use of the advanced techniques important as heating. Why then does the builder buy them? that have been developed. Such basic strengths help reduce Obviously, something’s wrong with us if we can’t get him to the price of the hydronic job to a more attractive level makbuy the heating system that even he admits is the best, and in ing the approach to the builder easier. Notice that I said “more most cases uses in his own home. attractive level.” I did not say that the hydronic price has to be In my opinion the thing that’s wrong with this is that we simequal to warm air. It can’t be except for some rare architectural ply don’t try. We trip over our own mental blocks. We create designs. Face the fact that a hydronic price is going to be higher Frankenstein monsters such as price and then run scared before than warm air although the actual difference can be narrowed we even face them. down by updating installation and design practices. Now, many contractors are going to say that they’ve tried The basic appeal to the builder is simple: he will make more to sell hydronics to builders. Well, talking to a builder about money by using hydronics. He will do this in two ways: hydronics in a weak, namby-pamby manner can hardly be called 1) selling. All they’ve done is converse with the builder. How By selling his houses faster. This means real money many contractors have even done this much with consistency? to a builder and you don’t have to explain it to him. It’s enough How many have approached the builder with a plan, or a proto say that if a builder sells homes fast; his profit is increased gram, or even an understanding of the builder’s problem? Yet by the amount of unused overhead, which he allowed for each they’re content to sit around calling house. This, plus his ability to move the builder names because he refuses into another job more rapidly are to pay the difference in cost between important factors to him. an air system and a hydronic sys2) By selling an upgraded tem. Well, why should he pay more product. Suppose a builder of a 15 for hydronics? Because Charley the home project upgraded his homes plumber is a nice guy? Or because with a hydronic installation that costs Charley talks about hot water heating him $250 more than the warm air job being better? he had intended using. (Sharp conYet if Charley talked about hydrontractors in many areas are installing ics helping the builder sell more homes, hydronics for only $100-$150 above and selling them faster, and if Charley warm air prices.) But he sells the gave good sound, tangible reasons for house for $500 more than he planned the benefits of hydronics instead of ($250 for the hydronics and $250 for beating his guns about the vague “qualhis own profit pocket). On a project ity” of hydronics, Mr. Builder would of 15 homes with an increased profit have better reasons to buy. of $250 per home Mr. Builder pockIdle, valueless quality means nothets an additional $3,750 profit. On ing to a builder. But functional quala 25 home job he picks up $6,250. ity—the kind that works for a builder On 50 homes $12,500. And if he’s means a whole lot. All ovens are small and builds only 3 homes per going to bake a cake. But the glass year $750 bucks isn’t bad either. Bear and chrome jobs look better while this in mind; his only investment is they’re baking. And almost all heating $250 for the hydronic system in the systems will pump a volume of heat model house. For this investment the into the house. But hydronics does it This ad ran in 1966 in HPAC and shows the ongoing 15-house builder picks up $3,750 or a better in many, many ways. Maybe if focus on attracting builders to hydronic heating. return on his investment of 1400%! If 28 | september 2013
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a builder wasn’t interested in hydronics before I think he would be after hearing that kind of profit story. And what better way to take the price tag off the hydronic job than to convince him of his huge profit potential with hydronics? The difference in cost between your system and the air job becomes peanuts. Now, someone is going to say that builders won’t raise the price of their homes by $500 to cover the profit and hydronic system. Well, why not? After all, any builder knows that the homeowner buys price ranges rather than flat price. In other words, a $21,000 house is still a $21,000 house even if it’s priced at $21,500 or $21,750 or even $21,990. Why then shouldn’t he shoot for the high-ticket sale? It’s extra bucks in his pocket. Beyond that, suppose the homebuyer did want to spend less. The builder could reduce the price of this one home and give the buyer a warm air system. This same formula has worked wonders for the automobile business in building the profit picture. Automatic transmission is the standard at a higher price. If a buyer wants a manual shift he can get it. But the auto dealers are upgrading first and only coming down when absolutely necessary. It doesn't make sense to do it any other way. I might add here that this is another reason why I am dead set against offering hydronics as an optional feature in the home. Sell hydronics as the standard system. Does this program work? Yes it does—it works beautifully. There's a progressive contractor by the name of Ed Pepling up in Northern New Jersey who used this plan to build an
extremely successful business. Ed does both warm air and hydronic heating so he really is in an excellent position to judge profitability. He also does plumbing. A couple of years back he took this concept and advanced it even further by offering to guarantee the builder the cost for hydronics on his model house. He approached builders offering to put hydronics in the model home at the cost of warm air. If hydronic heat didn't catch on with the builder's customers, and if he didn't sell the model house at the additional price, then Ed lost the difference. If hydronics pulled then Ed got his hydronic price. Did it work for him? Ed doesn't offer builders the no risk guarantee any longer. He doesn't have to because his builders want hydronics as their standard heating system. It's even affected the custom home market in his area to the point where also every custom home gets a hydronic system. In 1962 Pepling Plumbing and Heating did over 100 homes with hydronics and he got the plumbing as well. I could go on and on with other case histories to prove that contractors can sell builders on hydronic heating in volume despite the higher cost. But, they can't do it sitting around shaking their heads. Mr. Buschel is vice president sales, Slant/Fin Radiator Corp.
Editor's Note: This article first ran in April 1964 in Automatic Heating/Plumbing/Air Conditioning, later renamed Heating Plumbing Air Conditioning (1965).
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>> Efficiency
Capitalizing On Greening It takes more than technology to produce results.
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ur industry has contributed to substantive change to help make this planet a bit greener and cleaner. There are truly a myriad of examples. Plumbing fixtures are using much less water and we are seeing more and more options to recycle grey water. Variable speed pumps and motors in HVAC equipment are becoming the norm resulting in vastly reduced electrical consumption. Newer, more environmentally-friendly refrigerants have replaced the ozone depleting varieties of the past, in addition to vastly improved handling and disposal practices. The equipment running these refrigerants has also improved electrical efficiencies. All in all, not a bad list. Let’s move on to the true environmental villains, the fossil fuel burning, carbon spewing appliances that are heating up our homes in the winter and our hot baths and showers all year long. How are we doing on that front? That is the segment of our industry that I have the most experience with and I can say
Perception versus Reality
Let me start right out of the gate by stating that the views expressed herein are mine alone and do not necessarily reflect the opinions of HPAC Magazine, its editors or publishers. Now that we are clear on that, allow me to go on a bit of a rant here. I do not want to give anyone the impression that I am a miserable old complaining curmudgeon but sometimes I just have to blow off a bit of steam. This time it is the hypocrisy of the whole “Green” industry that has raised my ire. Do not get me wrong, I believe we all need to be as environmentally conscientious as possible, but unfortunately it seems more often than not the perception of “being green” is more important than actual results or performance. In just about every situation I prefer to opt for substance over appearance but this world seems to operate the other way around. Perhaps I am just grumpy because I happen to earn my living and pay my taxes and my Hydro bills in the province of Ontario, the province that has, in the words of Al Gore “the single best green energy program on the North American continent.” One might think this would be a good thing and if it were even remotely accurate it certainly would be. However, the truth is a little bit inconvenient, to steal a phrase. Ontario’s Auditor General came to the conclusion that several generations of the provinces taxpayers will have to deal with billions of dollars in extra hydro charges for years to come as a result of the Green Energy Act — the smoke and mirrors environmental legislation Dalton McGuinty and his cronies cooked up. Quite the legacy for the former Premier, who also managed to kick the taxpayer one more time on his way out the door by flushing close to a billion dollars down the drain via the cancelled gas plant contracts. 30 | september 2013
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it is the area where we have really made great strides forward. The good news is that when it comes to fossil fuel burning combustion equipment, whether it be hot water heaters, boilers, furnaces or make up air units, we do have the technology to utilize the fuel efficiently, extracting virtually all of the energy. We can also do it cleanly, emitting little more than water vapour. I have seen condensing boilers operate at near 100 per cent efficiency, with icy cold return temperatures from a snowmelt system nearly matching the temperature of the flue gas exhaust. This is an extreme example and not the normal operating conditions of the average heating boiler or furnace, but the point is that the technology exists here and now to utilize the fuels as efficiently as possible. Do I hear a but? On the other side of the coin, while the technology exists and is readily available, it is not always being utilized, or it is not being utilized properly. I have seen tender plans for buildings designed to achieve various levels of LEED status and yet the specified boilers are large inefficient atmospheric boilers, usually seriously over-sized. What kind of Leadership in Energy Efficient Design is that? Yes, we have improved minimum efficiency requirements for this type of equipment but I do not feel we have gone far enough or fast enough. But minimum efficiency standards are just one part of the equation. Simply installing a piece of high efficiency equipment does not guarantee savings. Systems have to be sized, designed, applied and controlled properly if maximum results are to be achieved. We regularly see fuel savings of at least 35 per cent and often much higher when older systems are upgraded properly. If we could extend those savings to all of the 650.9 Megalitres of natural gas that were burned in Canada last year alone strictly for residential purposes that would be something that even David Suzuki could be happy about. Fortunately, we also living in a time where information is shared and exchanged faster and easier than ever. Teaching and support resources are readily available through wholesale partners, manufacturers and their sales agents. The internet is also a boon, full of information but also lots of misinformation so use with caution. If you are a contractor who wants to be a part of the greening of our world the resources are available to help you get there. Steve Goldie is with NEXT Plumbing Hydronics where he is the hydronics specialist. He learned his trade from his father while working as a plumber in the family business. He joined the wholesale side of the business in 2002 after 21 years in the field. Steve is frequently called on to troubleshoot systems and advise contractors. He can be reached at sgoldie@nextsupply.ca.
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