HVAC Portfolio

Shubham Solanki | PG 180982 HVAC Lab M.Tech Building Energy Performance

CEPT University April 2019 Spring Semester Shubham Solanki

HVAC Lab

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Tracer Decay Method Co2 Decay Morning

The Dry Ice was used to conduct and experiment to fin d the Air change rate due to infiltration.

The intial Co2 concentration inside it was 5000 ppm and outside it was 400 ppm.

HOBO MX Co2 was used to measure the concentration .

The LN (Co2 In -Co2 Out) vs Time graph is plot

LN (Co2 In -Co2 Out)

Intent

8.30 8.10 7.90 7.70 7.50 7.30 7.10 6.90 6.70 6.50 12.00

y = -0.2747x + 11.453 R² = 0.9957

12.50

13.00

13.50

Inference

Slope of line = .012= Air change rate per hour during the night time.

The Decay in the morning is higher, due to high pressure and outside temperature.

This can also be taken care while calculating the load of the HVAC system

15.00

15.50

16.00

16.50

7.50 7.30

7.10 6.90 y = -0.1251x + 7.3289 R² = 0.9947

6.70 6.50 0.00

Shubham Solanki

14.50

Co2 Decay Night

LN (Co2 In -Co2 Out)

Slope of line = .0.28= Air change rate per hour during the day time.

The infiltration shows the air tightness of the room.

14.00

0.50

1.00

1.50

HVAC Lab

2.00

2.50

3.00

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4.50

5.00 2

ERV PROTOCOL OBJECTIVE OF THE MEASUREMENT The ERV installation is done keeping the following four objectives in mind:• To check the efficiency of the heat exchanger inside the ERV. • To check the efficiency of the entire system

• Reduction in Air Conditioning Loads due to ERV • Check the indoor air quality in absence of and presence of ERV

ERV Section and Dimensions Shubham Solanki

HVAC Lab

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ERV PROTOCOL MEASURES OF METRICS USED

ERV Installation Schedule

The efficiency of the system was checked using the following formula.

1. Ρ =đ?‘‡â„Žđ?‘–−đ?‘‡â„Žđ?‘œđ?‘‡â„Žđ?‘–−đ?‘‡đ?‘?đ?‘– where, Thi = Temperature of heat indoor

Tho = Temperature of heat outdoor Tci = Temperature of coolth indoor

2. Total Effectiveness (Abs(TotEff )) = (SMFOut *( SHIn SHOut))/(MinMF*( SHIn - EHIn)) where, SMFOut = Supply Air Mass Flow leaving ERV/delivered to building, lb/h SHIn = Supply Air IN Enthalpy, Btu/lb SHOut = Supply Air OUT Enthalpy, Btu/lb MinMF = Minimum of SMFOut and EMFIn values

Instrument Used

EHIn = Exhaust Air IN Enthalpy, Btu/lb

3. COP of HX = Desired Output/Required Input = Cooling Effect/Work Input TSI Alnor Balometer and Micromanometer Shubham Solanki

HVAC Lab

HOBO MX CO2 Logger MX1102

HOBO U12 – 012 DATA LOGGER

CURRENT TRANSDUCER 4

Blower Door Test Intent The objective is to conduct Blower Door test and to take one set of measurements.

Install the Minneapolis Blower Door with DG-1000 and mention the testing protocol, precautions and configuration of ports.

Blower door fan with connection.

Testing Protocol • All windows, ventilators and any other doorways or openings to be closed completely.

• All air-conditioners and fans are to be switched off while testing • Any combustion appliances are to be turned off during test • Any ducts or vents with possible openings are to be closed but not sealed beyond intended infiltration.

DG-1000 with port connections in place.

Installing the framework into the doorway.

Shubham Solanki

HVAC Lab

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Blower Door Test Precautions

Configuration of Ports

• While fixing the frame, it is important to tighten the knobs firmly to the doorway to ensure that the size of the adjustable frame does not get altered while fixing the nylon panel

• The configuration of the tube is based on the gauge that is used to record readings.

The gauge used for this experiment is the DG-1000 gauge.

• Ensure that the nylon panels are fastened with Velcro to avoid gaps between the panel and the frame.

• It is important to make sure that the cam levers are used to completely seal the doorway position to ensure that there are no air-gaps between the frame and the door way.

• The crossbar must be installed to ensure that excessive tightening of the frame knobs does not bend the frame and hence cause air gaps in the installation

• While placing the blower fan, it is important to make sure that the elastic of the nylon panel hole is completely wrapped on the panel collar of the blower fan.

• The Velcro tab holding the fan and the crossbar must be tightened such that the fan is two inches above surface and it is also important to ensure safety of the blower fan.

• Precautions are taken during recording of data to ensure that the data is recorded only when the readings have stabilised considerably.

• While conducting the blower door test, it is important to note that there must not be any obstructions in front of the exhaust fan as this will affect the flow of the blower fans which may lead to unstable readings.

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• The gauge consists of four input taps to which the tubing can be connected.

• The input taps are categorised as Channel A and Channel B with two input taps assigned for each channel. One of which represents an input tap and the other represents a reference tap.

For depressurisation o The green tubing is connected to the reference tap of channel A on one end and the other end of the tube is passed outside through the nylon panel.

For pressurisation o The position of blower fan is reversed. o The green tubing is connected to the reference tap of channel A on the gauge and the other end of the tube is placed indoors of the room need to be tested kept away from the exhaust. o The red tube is connected to the input tap of Channel B on the gauge and the other end is connected to the tap at the input of tap near the power supply socket. o The White tube is connected to the reference tap of channel B and passed through the hole in the nylon panel to the outdoor area.

o The red tube is connected to the input tap of channel B on the gauge and the other end is connected to the tap at the input tap near the power supply socket

HVAC Lab

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System Schematics with Measurement & Evaluation Plan Intent Draw a schematic of the HVAC system and propose the Measurement and Evaluation plan for the same

Refrigerant + Water Loop of the System

System Chilled Water System – The chilled water system comprises of two water-cooled chillers and primarysecondary chilled water pumping systems. Each chiller is served by a dedicated constant speed primary pump. The secondary pumping system comprises of two variable speed pumps.

Condenser Water System Condenser water comprises of two cooling towers. Each cooling tower is served by a dedicated constant speed condenser water pump.

Shubham Solanki

HVAC Lab

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System Schematics with Measurement & Evaluation Plan System

Refrigerant + Air Loop

Air System – Air System comprises of Variable Air Volume Air Handling Unit (with cooling coils) serving Fan Powered Constant Air Volume Terminal Systems with Cooling Coils in the terminal unit.

Measurement & Experimentation plan Objectives :To measure the effectiveness of DOAS with ER Wheel Determining the Percentage of Outside Is sufficient or not Metric Used 1. % outside air =return air temp – supply air temp/return air temp – outside air temp x 100 Air flow (cfm or m3/h) × %OA /100 = OA% cfm or m3/h To Determine amount of fresh air is sufficient for the people No. of people = OA% cfm / volume of OA per person

Shubham Solanki

Determining the Percentage of Fresh Air Equipment Status Logger Type Cooling On + HOBO U- 12 & DOAS on TM6HD probe HOBO U-12 & TM6HD probe DOAS Off

HVAC Lab

Logging Position

Objective To measure the Temperature and AT 3 Zones of DOAS Rh.This will help to find Outside air %. Effectiveness of DOAS in sensible AT 3 Zones of DOAS and latent load.

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System Schematics with Measurement & Evaluation Plan System

Air Loop

Fresh Air System – Dedicated Outdoor Air System with Energy Recovery Wheel is connected to Air Handling Unit fresh air duct on each floor.

2. To measure the effectiveness of DOAS with ER Wheel Metric used Effectiveness of DOAS = Fresh air Enthalpy – Supply air Enthalpy / Fresh air Enthalpy – Return air Enthalpy

DOAS efficiency = Cooling Delivered / power consumed

= (M x Cp x dT) + (M x Lv x dH) / V x I x pf

M= Mass flow rate , Cp = Specific Heat of air , Lv = Latent Heat of evaporization , dT= TR- TA, dH = Humidity ratio (Return – Supply) , V = Voltage, I = Current, pf= Power Factor

Shubham Solanki

To measure the effectiveness of DOAS with ER Wheel Equipment Status Logger Type Cooling On HOBO U- 12 & +DOAS on TM6HD probe HOBO U-12 & DOAS Off TM6HD probe Onset CT + HOBO U-12 HVAC Lab

Logging Position

Objective

AT 3 Zones of DOAS To measure the Temperature and AT 3 Zones of DOAS Rh.To calculate the total heat.

Live Wire To measure the current 9

System Schematics with Measurement & Evaluation Plan Determining the Percentage of Outside Is sufficient or not Measure the reading or every 15 min for 24 Hours. Measure the CFM using Balometer.

Equipment Status Logger Type Cooling On + HOBO U- 12 & DOAS on TM6HD probe

Logging Position Return and Supply of AHU Live Wire at chiller Onset CT + HOBO U-12 and AHU

COP = Cooling delivered by AHU / Power consumed by (AHU + Chiller) Cooling Delivered = (M x Cp x dT) + (M x Lv x dH)

Objective To measure the Temperature and Rh.To calculate the total heat To measure the current

Instrument used

M= Mass flow rate , Cp = Specific Heat of Water , Lv = Latent Heat of evaporization , dT= TR- TA, dH = Humidity ratio (Return – Supply) Power = V x I x pf V = Voltage, I = Current, pf= Power Factor

Precautions For the correct measure and calculation consider the accuracy and Before measuring check the battery.

Recheck the logger after 10-15 before final measurement.

Co2 sensor should be placed away from the occupant.

The Hood should be covered avoiding the air leakages.

While using the CT take help of the electrician supervisor and don’t touch the wire

Shubham Solanki

HVAC Lab

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Set-point definition and Comfort models Natural ventilation-Adaptive Band Location – New Delhi

Daily Comfort Band - Adaptive NV model

Daily comfort band (NBC 2016 Adaptive NV model)

35.00

Indoor operative temperature

32.50

= 0.54 x Outdoor temp x 12.85

And it was used to calculate the Neutral temp. , NV + Band and NV – Band.

30.00

Temperature ⁰C

The 90 % acceptability range for the India specific adaptive models is ± 2.38°C.

27.50 25.00 22.50 20.00 17.50

15.00 0

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Axis Title

New Delhi Neutral temp. NV Buildings

Shubham Solanki

HVAC Lab

New Delhi NV+ band

New Delhi NV- band

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Set-point definition and Comfort models AC-Adaptive Band

Daily Comfort Band - Adaptive NV model

Location – New Delhi 35.00

Daily comfort band (NBC 2016 Adaptive AC model)

32.50

Indoor operative temperature

30.00

The 90 % acceptability range for the India specific adaptive models is ± 1.5°C.

27.50

This formula was used to calculate the Neutral temp. , NV + Band and NV – Band.

Temperature ⁰C

= 0.078 x Outdoor temp x 23.25

25.00 22.50 20.00 17.50 15.00 0

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Axis Title

New Delhi Neutral temp. NV Buildings

Shubham Solanki

HVAC Lab

New Delhi NV+ band

New Delhi NV- band

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Hvac System analysis and Energy conservation measures Base Case Model ECBC prescriptive base case models •Floor :3 •Floor plate size : 32m x 16m •Longer Axis : East - West •Zoning : 4m deep perimeter zone •WWR : 30% VRF System Building module

• Base case • CoP of the cooling system is 3.3 • AHU is connected for Fresh air inlet to the zone. CAV Fan with Efficiency 70% and pressure rise 600 Pa • Fan Coil unit serving at each zone on all three floors •

Heating is turned off

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HVAC Schematic

HVAC Lab

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Hvac System analysis and Energy conservation measures Base Case Model Summary EPI – 135 kWh /sqm Total Cooling Electricity Consumption – 111.70 kWh Total Cooling Fan Electricity Consumption - 75.1 kWh

AHU Air Nodes Temperature 45

40

35

Time Set point Not Met During Occupied Cooling - 1492.5 Observation The Air temperature of Supply air is slightly higher then the fresh due to heat added by the fan.

It can be observe that during summer time the return air is very low and is being wasted and send to environment without being reused.

The Fan Electricity consumption is very high and can be reduced using the higher efficiency fan.

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25

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Summer Time 15

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1 205 409 613 817 1021 1225 1429 1633 1837 2041 2245 2449 2653 2857 3061 3265 3469 3673 3877 4081 4285 4489 4693 4897 5101 5305 5509 5713 5917 6121 6325 6529 6733 6937 7141 7345 7549 7753 7957 8161 8365 8569

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Return Air

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HVAC Lab

Fresh Air

Supply Air

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Hvac System analysis and Energy conservation measures Objective – To reuse the Return air to Decrease the load and EPI and Reduces the load on VRF. What is the change after using the recirculation and heat recovery? Plot the Nodes temperature to check the difference.

CASE

Spatial

Energy

After the base case 2 ECM were Proposed to re-use the return air.

1. Recirculation 2. Heat recovery Wheel

Building AHU(CAV)

EPI/Cooling Electricity

Case 1

AHU Schematic Case 1

There is No Recirculation No Heat recovery , Only fresh air supply

Shubham Solanki

Environment Outdoor Temperature,Nodes temperature and Humidity Ratio

Case 2

AHU Schematic Case 2

There is only Recirculation Circulation, No Heat recovery

HVAC Lab

Comfort Met/Unmet hours, NBC AC-2016 Adaptive

Case 3

AHU Schematic Case 3

The Recirculation and Heat recovery is on

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Hvac System analysis and Energy conservation measures

Mixed Air Temperature

Observation 45.0

The Air without any mixing is at the same temperature as that of outside air temperature

35.0

Temperature (⁰C)

We can observe the Using recirculation and heat recovery wheel the mix air temperature is lowered to 32⁰c during summer time. And 26⁰ C - 28⁰c while using the heat recovery.

40.0

30.0 25.0 20.0 15.0

Summer Time

10.0

Mixed Air (N-C)

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HVAC Lab

01-01-2003 00:00

01-12-2002 00:00

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5.0

Time

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Hvac System analysis and Energy conservation measures Case 3 The point on the chart is the marked for the 12 June at 4 pm

Process 1

3 + 2

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2.

3.

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4 Fresh Air Mixed Air Return Air Supply Air

The fresh air comes in contact with heat inside the Ahu and Return air and the final air is supply air to the zone.

The heat recovery reduces the humidity ratio leading to reduction in latent load.

Shubham Solanki

4 3

1

2

Psychometric chart of case 3 on 12 june at 4 pm

HVAC Lab

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Hvac System analysis and Energy conservation measures Unmet hours

The core zone was plotted because it have the maximum Unmet hours. if they are comfortable in this Zone then they will be comfortable in all the other zones.

The band is NBC-Adaptive Ac Set point. The operative set point was 24,25 and 26â °C

Unmet Hours

Comparison between variable set point and constant set point

We can observe that the comfortable hours within the band and maximum are near to the neutral axis. In the month of June there are more uncomfortable hours.

450 445 440 435 430 425 420 415 410 405 400 Variable Set point

Set point Type

Comparison of Variable and constant set point unmet hours

Total Energy 120000

The VRF system with Heat recovery and recirculation was optimized using the variable set point to reduce the EPI according to NBC Adaptive -AC set point.

100000

But the reduction in energy is 32%.

Energy ( kWh)

And reaching till 28.5 â °c

We can observe that the difference in unmet hours is of 26 hours higher in case of Constant set point.

80000 60000 40000 20000 0 Variable Set point

Constant Set point

Set point Type

We can use this as an ECM. Shubham Solanki

Constant Set point

HVAC Lab

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All Floor Core zone- Operative Temperature

All Floor core zone

31.0 31 31 31.0

We can observe that highest uncomfortable hours are in case of second floor core zone and lowest on the ground floor.

29.0 29 29 29.0

27.0 27 27 27.0

Operative - Temperature (â °C)

The air temperature during this time is set on 26â °

25.0 25 25 25.0

23.0 23 23 23.0 Summer Time

21 21.0 21.0 21

Hourly operative temperature Ground floor Core zone 19 19.0 19.0 19

Hourly operative temperature First floor Core zone Hourly operative temperature Second floor Core zone

17 17.0 17.0 17

15 15.0 15.0 15

Time All Floor Core zone- Operative Temperature on the NBC- Adaptive AC band

Shubham Solanki

HVAC Lab

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Thank you Shubham Solanki shubham.pg180982@cept.ac.in

15-04-2019

Shubham Solanki

HVAC Lab

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