BOILERS Treating water to reduce mechanical load and energy use

from Mechanical Business March/April 2022

HIGH-PERFORMANCE HVAC Focus on glazing

Will Wilson manages the sustainability division of Pace Solutions in Delta, BC. His focus is on educating the market on innovative solutions to achieve building energy efficiency and emissions reductions.

TREATING WATER TO REDUCE MECHANICAL LOAD AND ENERGY USE

Hydronic systems are the most common commercial space heating system used in the northern hemisphere. Space heating represents the largest energy use in buildings, consuming more than seven trillion Joules of energy in the U.S. alone. Along with high utility bills, energy use is often directly linked to the efficiency of the mechanical systems cycling the water. However, replacing existing mechanical systems with more efficient modern equipment can be cost prohibitive, leading some to wonder, “What if we improved the efficiency of the water instead?” Over the past 30 years, a significant focus has been on the use of surfactant additives to reduce surface tension with the goal of improving heat transfer between the system water and the heating unit. Typical heating units include radiators, fan coils or heat exchangers. Studies have shown that surfactants improve heat transfer, but long-term temperature stability remained the barrier in their efficacy in commercial systems. Recent advancements in non-ionic surfactant technology have produced a stable additive that is not susceptible to breaking down in commercial HVAC systems. Solving the stability issues has allowed for broad scale testing and case studies. The results show an increase in heat delivery, a decrease in system cycling, and greater energy efficiency with reductions in energy consumption of up to 15 per cent.

energy in with high is often fficiency of cycling the ing existing

h more ment can be g some to mproved the instead?” a signifithe use of reduce sur- Replacing aging equipment with more energy-efficient mechanics is a costly oal of improving endeavour, especially for older systems running on tight operational budgets. he system water ypicalheatingunitsincluderadiators HOW NON-IONIC SURFACTANTS WORK HO Hydronic systems transport water or a water/glycol mixture through pipes to provide heating and cooling in a building. Water’s naturally high surface tension creates laminar flow along the boundary layer, trapping an insulating layer of water in micro-imperfections on the surface. The insulating effect sequesters the heat to the centre of the stream, hampering proper heat transfer as shown in Figure 1. The system consumes excess energy and generates more emissions as the demand

Figure 1 - Improvement to heat exchange

Figure 2 - Time and fuel required to reach set points

on mechanical components to deliver heat increases. Surfactants reduce surface tension facilitating better contact with the surfaces, increasing heat transfer, resulting in increased efficiency and reduced run times (see Figure 2). The system em will hit set-points faster and run less frequently to to maintain ambient temperatures. eratures Specific surfactants are compatible with glycol and corrosion inhibitors and require no changes to the system. The concentration of a non-ionic surfactant should remain at around one per cent with annual testing recommended. Installation of the additive is a one-person task, requires no downtime and, in most cases, involves no extra equipment. Barring significant leaks causing a reduction in concentration, installations have shown to be effective for up to 10 years.

AN OPTION TO COSTLY RETROFITS

Space heating represents the largest energy usage in buildings and generates a large percentage of global emissions. Surfactants are an option to lower building energy consumption and emissions without the need for costly retrofits. Non-ionic surfactants are also noted to be less corrosive than water, compatible with common system materials and traditional corrosion inhibitors. Look for a surfactant that has no impact on the freeze protection of commonly-used glycols and one that has been verified by major boiler manufacturers. Testing has shown some surfactants to be thermally stable, allowing for years of improved heat transfer and energy efficiency in hydronic HVAC systems. Enhanced water efficiency decreases the number of cycles required from pumps, lowering electricity costs. It also improves T, requiring less burning of fossil fuels to heat the water, decreasing emissions and further lowering utility costs. All of this together can mean a short payback with no downtime and a dramatic improvement to the building or facility’s carbon footprint.

CASE STUDY: UNIVERSITY OF BRITISH COLUMBIA DISTRICT HEATING NETWORK

The University of British Columbia (UBC) tested a non-ionic surfactant to determine the improvement of T (Delta T - the difference between supply water temperature and return water temperature) inside a secondary system on the university’s district heating network. The Horticulture Building within the UBC DES system is set up with 15-minute monitoring on flow/return temperatures, internal comfort conditions, and external ambient air temperatures to allow the variable flow valve to open/close dependent on the demand and weather conditions.

The goal was to monitor the additive’s impact on the system’s T and verify if the additive could improve heat transfer. The test also monitored the valve position (VF) at the heat exchanger, recording building demand compared to outside temperature (see Table 1). Results of testing showed the non-ionic surfactant reduced the average valve position creating a reduction in the electrical workload of the pump to maintain the comfort conditions required in UBC’s district energy system.

Table 1– A comparison of system Ts at known valve positions.

Sue Sodek has over 20 years of human resources and consulting experience across a variety of businesses, and currently manages HR for UCEL Inc in Uxbridge, ON. She can be reached at sue.sodek@gmail.com.

How to get a worker off the injured reserve and back on your roster

While we would all agree that accident prevention and building a culture of “safety first” is the ideal, the reality is, as long as you have people doing the work, there will be injuries on the job. Learning how to help employees get back to productive work after an injury is a skill all managers must rely on at one time or another. Since no two incidents are quite the same, you’ll need to work with not only your employee, but possibly their doctor, the health and safety body in your jurisdiction, your supervisors, and the rest of your team when you’re formulating a plan to get an injured worker back on the job. When an employee is hurt and loses time at work, it can make for a high stress time for both them and the company. The first priority of course is getting the worker medical assistance, and aiding them in whatever way is most needed by providing transportation to a hospital or doctor, contacting family members, arranging to secure and deliver their personal belongings or vehicle home, anything else so they have one less worry. Whenever possible, talking to the employee directly is the easiest and best way to know what would be the most helpful in each situation. After an injury at work, as an employer you have a variety of reporting and tracking obligations in order to ensure that you remain in compliance with local workplace safety insurance legislation. These obligations vary slightly by province, so if in doubt check with your provincial authority. Beyond the initial reporting and paperwork though is your obligation (and interest) in getting that person back to work, usually as quickly as possible. In these days of labour shortages and record sick days, the last thing any company needs are seasoned workers sitting home idle. While every case must to be considered individually, there are some basic steps managers should follow when bringing back a worker who has been off due to an injury, and some common places where companies often get tripped up while navigating the process. our ed

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STEP ONE

Identify the essential functions of the job.

The simplest way to understand what tasks are essential to a job is to start with the basics. A plumber works with pipes, an electrician with wiring and a mechanic with machines. What are the role’s essential tasks? For most skilled trades, operating a vehicle, manipulating tools, and communicating with others are likely on the list as well. Now think beyond those tasks to the physical demands of

these essential components. For example, someone who installs and maintains residential furnaces probably cannot do their job without the ability to climb stairs, bend at their knees, or use their hands. How much bending, lifting, or kn standing are required on a daily (or hourly) basis for the job? st Are there repetitive motions that may be required, which A could aggravate or lead to further injury? Once you have a co solid grasp of the physical demands, you can start to look for so modifications, depending of course on the limitations of the m injured worker. in

Common error: Failing to narrow down to the C essential functions of the job. e

When crafting job descriptions, I’ve noticed many managers include every possible task and eventuality they can conceive a person performing, all under the heading of must do when of course most roles can be boiled down to four or five critical tasks (at most). Make sure you are keeping this in mind when you start to investigate and build your back-to-work plan. Keep to the essentials and focus on what’s required at a basic level. earnings. This can mean anything from modifying their current job or offering an alternative position for the short- or long-term. Common modifications include what’s termed light duties – meaning where possible, the physical demands of a role are eased or removed (less lifting, less travel time, or work performed sitting instead of standing). Depending on the size of your company, this may also mean moving someone who is normally in a more physically demanding role to one where they take on more administration, allowing them time to heal on the job while still earning and contributing.

Modifications are a legal obligation for all employers, but only up to the point that they cause undue hardship for your business. For example, you can and should offer someone with a broken leg work that allows them to sit where possible. However, you are not obligated to create an entirely new, unnecessary role, or to invent “busy work” just to keep someone employed. The size of your business and workforce may play a role here, and not every company has the ability to offer light duties. This may be an opportunity for vocational training, assigning partners or project work, or you may be forced to reduce hours until the worker is back to full strength. Each case is different, and openly communicating with your employee is key.

STEP TWO

Identify the barriers to performing those essential functions and possible alternatives.

The work, the individual, the severity of the injury, the amount of time needed for recovery all factor into and impact return to work discussions. Again, while each case should be weighed on its own merits, there will likely be some tasks a person can still complete, and some that will have to be modified or delegated until the worker is back to full functionality. Communicate with your employee. They may be anxious (and missing their paycheque). Ask them to share their thoughts and let them know you are open to working out a plan for their safe return. In general, workers who have been injured on the job need to be offered work they are qualified and able to do, and which allows them to maintain (or at least approach) their usual with yo you the r e r op

ome ified or erisbacktofull Common error: Failing (or refusing) to meet with the affected employee in a timely manner.

There are solid legal reasons why you should keep in close touch with your injured employee, but it’s also good business and the right thing to do. Ask plenty of questions and be open to what your worker has to say. There can be suspicion on both sides of these conversations. Employees may worry they will be fired for being hurt, and employers may feel their workers are exaggerating symptoms and looking for extra vacation time. The best antidote is direct, open communication. You can’t make good decisions about what someone else is capable of doing without talking to them.

Common error: Failing to meaningfully Com investigate/explore alternatives. investi

This is a pitfall you definitely want to avoid. Legally, you must make every effort to work with your employee to try to find solutions to get them back on the job. If you dismiss every reasonable suggestion, and fail to offer any solutions of your own, you will land yourself fines and worse from WSIB, workers’ compensation board or applicable health and safety governing body. Communication and documentation, as always, is key here.

STEP THREE

Develop a plan and monitor it for effectiveness

Once you’ve talked to your r employee and determined d how their position can be modified (and equally importantly, how long the modifications are going to be in place), implement your plan and start to track whether it’s working. Set calendar reminders for yourself to check in at the end of day one, one, week one, month one and so on, so on, and document how things are progressing. areprogressing In many cases, workers themselves will let you know when they improve, but it’s your obligation to keep the lines of communication open and ensure a return to full duties happens as soon as they are able. Common error: Failing to keep detailed records.

We all wear so many hats over the course of our workday, and We alll wear keeping HR documentation up to date is never high on the k keepin to do list. There are quick ways you can do better at to d record keeping, and it doesn’t have to be formal or re time consuming. At a minimum, when you’ve had a verbal discussion with an employee, follow up with a brief email summarizing what was decided and you’ll have an instant record of your conversation. Keep copies of any documents sent or received from the WSIB, workers’ compensation board or applicable health and safety governing body or the employee, in the employee file for quick reference. r When the employee is ready to return to regular Wh duties, it’s always worth having a final conversation and duties going over the process as a whole: how they will avoid a going ove repeat of the injury, how they found the modifications, and if they repeatofthe i have any suggestions or improvements for the future. While we all hope not to need them, following these steps (and avoiding the common missteps) will protect your business and help you work your way back to a fully-functioning team.