field and laboratory tests of a smart efficient fan

Robert Mowris, P.E.Verified® Inc.

EEDAL’19 PresentationNovember 7, 2019

Field and Laboratory Tests of a Smart Efficient Fan Controller® with Fault Detection Diagnostics (FDD)

for Residential Cooling and Heating

2

Summary• HVAC systems in US are oversized and operate at

Part Load Ratios (PLR) of 13% reducing efficiency• Patented EFC® improves part load efficiency with

variable fan-off delays, FDD, and reliable power for smart thermostats

• Smart EFC algorithms can be deployed on smart thermostats and fans to improve efficiency

• California Utilities offer incentives for EFC® and 135,000 units have been installed since 2012

© 2019 Verified® Inc.

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Laboratory Tests• Tests were performed at Intertek® ISO-certified

laboratory used by manufacturers and USDOE to test HVAC equipment for US Efficiency Standards

• Cooling and heat pump efficiency tests were performed per ANSI/AHRI Standard 210/240 for Unitary Air-Conditioning and Air-Source Heat Pump Equipment and ANSI/ASHRAE Standard 37

• Gas furnace tests performed per ANSI Z21.47• Hydronic efficiency tests were performed per

AHRI Standard 840 for Unit Ventilators© 2019 Verified® Inc.

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Intertek® Base and EFC® Cooling TestsEFC® saves 6 to 30% due to low part load efficiency of base


0

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0 10 20 30 40 50 60 70 80 90Time (minutes)

Sens

ible

EER

* and

Pow

er (k

W)

EFC® variable delay EER*Base no delay "dry coil" EER*Total AC Power (kW)

Intertek Test Data3-ton Split ACTests ES-C-F-5 thru 30

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Base and EFC® Cooling Field TestsEFC® saves 10 to 24% due to low part load efficiency of base


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0 20 40 60 80 100 120 140 160 180 200 220 240 260 280Time (Minutes)

Sens

ible

EER

* and

Pow

er (k

W)

0

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60

70

80

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100

110

120

Tem

pera

ture

(F)

Base Sensible EER* EFC® Sensible EER*Total Power (kW) Outdoor Air Temperature °F

6 © 2019 Verified® Inc.

y = 0.0627x-0.5408

R2 = 0.9804y = 0.0418x-0.5711

R2 = 0.986

y = 0.0468x-0.6928

R2 = 0.9861

-15%

-10%

-5%

0%

5%

10%

15%

20%

25%

30%

35%

40%

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0Cooling Part Load Ratio (PLR)

Coo

ling

Ener

gy S

avin

gs (%

) . Intertek® wt. ave. cooling savings vs. dry coil

EFC® FDD field test savings vs. no delay wet coil

Intertek® cooling savings vs. wet coil

Intertek® EFC® impact on AC-only EER*

y = 0.009x-1.095

R2 = 0.8992Intertek® Test Data

Intertek® EFC® Cooling Savings vs PLREFC® saves 10 to 15% on cooling for average Part Load Ratios


0%

20%

40%

60%

80%

100%

0 10 20 30 40 50 60 70 80 90 100

Time (Minutes)

Gas

Fur

nace

Hea

ting

Effic

ienc

y

EFC® variable delay low-high speed fanBase 90-second delay low-speed fan

Intertek Test Data80% AFUE 69 kBtuh Pkg FurnaceTests EP-H-Low-High-7-8-15-30

Intertek® Gas Furnace Heating TestsEFC® saves 10 to 26% due to low part load efficiency of base


0%

10%

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0 20 40 60 80 100 120 140 160 180 200 220 240Time (Minutes)

Hea

ting

Effic

ienc

y (%

) .

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550

Tem

pera

ture

(F)

Base Efficiency EFC® Efficiency HX temp BaseHX temp EFC® OAT Base OAT EFC®

Base and EFC® Gas Furnace Field TestsEFC® saves 10 to 32% due to low part load efficiency of base


0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

0 100 200 300 400 500 600Time (minutes)

Gas

Fur

nace

Effi

cien

cy (%

)

0

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50

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90

Tem

pera

ture

(F)

Base Efficiency EFC® HSF Efficiency Tstat EFC® °FTstat Base °F OAT Base °F OAT EFC® °F

Base and EFC® Gas Furnace Field Tests17.9% normalized EFC® savings 33.7F ∆T vs base 31.5°F ∆T


y = 0.0674x-0.4394

R2 = 0.955 y = 0.0612x-0.4733

R2 = 0.9628

0%

5%

10%

15%

20%

25%

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0Gas Furnace Part Load Ratio (PLR)

Gas

Fur

nace

Ene

rgy

Savi

ngs

(%)

Intertek® wt. ave. tests gas furance

EFC® FDD field tests wt. ave. v. base

Intertek® EFC® tests vs. 30 through 150-sec. base

Field tests EFC® FDD v. 90- and 120-sec. base delay

Intertek® ave. med speed 90-sec base

Intertek® EFC® Furnace Savings vs PLREFC® saves 10 to 20% on heating for average Part Load Ratios


0.0

0.5

1.0

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2.0

2.5

3.0

0 20 40 60 80 100 120 140 160Time (Minutes)

Hea

ting

CO

P an

d Po

wer

(kW

)

EFC® Variable Delay HP Heating EfficiencyBase No Delay HP Heating EfficiencyTotal Power (kW)

Intertek Test Data1.5-ton Heat Pump HeatingTests GF-HP47-2-5-10-20-30-50

Intertek® Base and EFC® Heat Pump TestsEFC® saves 5 to 31% due to low part load efficiency of base


y = 0.0591x-0.4341

R2 = 0.9194

0%

5%

10%

15%

20%

25%

30%

0.0 0.2 0.4 0.6 0.8 1.0

Heat Pump Heating Part Load Ratio (PLR)

Hea

t Pum

p H

eat E

nerg

y Sa

ving

s (%

)

Intertek® Wt. Ave. HP heating savings 0 and 65-sec. base

Intertek® HP heating savings no delay base

Intertek® HP heating savings 65-sec. delay base

Intertek® Test Data

Intertek® EFC® HP Heating Savings vs PLREFC® saves 5 to 36% on HP heating for average Part Load Ratios


0%

10%

20%

30%

40%

50%

60%

70%

80%

0 20 40 60 80 100 120 140 160

Time (Minutes)

Hyd

roni

c H

eatin

g Ef

ficie

ncy

(%) EFC® variable fan-off delay efficiency

Base No fan-off delay efficiency

Intertek Test Data1.5-ton Hydronic HeatingTests GF-HYD130-2-5-10-20-30-50

Intertek® Base and EFC® Hydronic TestsEFC® saves 3 to 32% due to low part load efficiency of base


y = 0.0420x-0.6667

R2 = 0.9597

0%

5%

10%

15%

20%

25%

30%

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Hydronic Heating Part Load Ratio (PLR)

Hyd

roni

c H

eatin

g En

ergy

Sav

ings

(%)

Intertek® Wt. Ave. Hydronic heating savings 0 and 60-second base

Intertek® Hydronic heating savings zero delay base

Intertek® Hydronic heating savings 60-second delay base

Intertek® Test Data

Intertek® EFC® Hydronic Savings vs PLREFC® saves 4 to 34% on hydronic heat for average Part Load Ratios

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California HVAC Market Share Estimate

Building Type

AC with Gas Furnace

HeatHeat

Pump

AC with Hydronic

Heat

AC with Electric

HeatMulti-Family 49% 40% 9% 2%Single family 88% 9% - 3%Mobile Home 89% 10% - 1%


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• EFC® average cooling savings are 11.3 ± 2.7% • EFC® average gas furnace, heat pump and

hydronic heating savings are 14.4 ± 1.6%• Potential EFC® savings in US are 0.96 quads (1 EJ)

based on 8.2 quads (8.6 EJ) for HVAC end uses• Smart EFC® improves HVAC part load efficiency• New transient test procedures are required for

codes and standards to capture EFC® savings

Conclusions


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Robert Mowris, P.E., Verified® Inc.

Thank you!


field and laboratory tests of a smart efficient fan

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