Performance Testing numbers: Good or Bad

[GoHuskers]

Hello experts,

My installer finally did the performance test for my unit and here are the numbers:
Brand: HeatController - Comfort-Aire
Model: HTV036B1C01JLK - 3-ton
Type: Water to Air, closed loop 1200' total, antifreeze filled in tubes

HEATING Mode:
Voltage: 242
Water In Temp: 50
Water Out Temp: 43
Temp Change: 7

Pressure In (lbs): 24
Pressure Out (lbls): 13
Pressure drop: 11

Return Air Temp: 68
Supply Air Temp: 95
Temp Change 27

COOLING Mode:
Voltage: 244
Water In Temp: 44
Water Out Temp: 52
Temp Change: 12

Pressure In (lbs): 24
Pressure Out (lbs): 13
Pressure drop: 11

Return Air Temp: 66
Supply Air Temp: 39
Temp Change 27

These numbers were collected when HWG is OFF. When HWG is ON, the Water Temp In is 40 and Water Temp Out is 39

What do these numbers tell us about our system? He wanted to use the Manufacture list Flow Rate (GPM) for the pump but I insisted that he must test it and use that number instead. The pump is manufactured by bdmfginc, model QT Flow Center 2-230QFC.

Thank you.

[Bergy]

These numbers can't be correct. According to page 16 of the Engineering Design Guide ( http://www.comfort-aire.com/download...age-geothermal ) 5.2 PSI drop through the exchanger equals 9 GPM.
11PSI drop @ 50* EWT equals about 18 GPM. If the numbers are correct the system is WAY over pumped. I also don't see how 18 GPM can still give you a 7* Delta T. With your numbers...

18 GPM X 7* Delta T X 485 = 61,110 Btu's Heat of Extraction
The Spec Guide shows a HE of 31,700 Btu's @ 50* EWT W/9 GPM

According to the numbers a 7* Delta T W/9 GPM @ 50* EWT would equal 30,555 Btu's, very close to the spec value of 31,700 Btu's

[GoHuskers]

Thank you SO MUCH for your reply, Bergy. This is why I came to this site, so many knowledge people here. I know something is NOT right with my system but I don't know what is wrong.

What is your suggestion that I should look into? Thanks.

[Nuclrchiller]

Was a single gauge and a single thermometer used for the water pressure and temperature measurements? Doing so will eliminate the possibility of gauge/thermometer error causing in incorrect measurement of one the pressures/temperatures that will result in a faulty calculation of pressure drop or temperature change.

[GoHuskers]

Was a single gauge and a single thermometer used for the water pressure and temperature measurements? Doing so will eliminate the possibility of gauge/thermometer error causing in incorrect measurement of one the pressures/temperatures that will result in a faulty calculation of pressure drop or temperature change.

The tech used the push-type meter that he pressed it thru the P/T plug (I guess) and measured the water temp/pressure. For air temp he poked 2 holes in the vent-tube and inserted a stripped copper wire that connected to a temp-meter (I guess) to measure that.

He did NOT measure the flow rate (GPM) because he did not have the tool at that time - will be done tomorrow.

Thanks.

[crmont]

How close is the pump to the inlet pressure port?

[Bergy]

If you have a non-pressurized loop there is a "Flow Gauge" that's inserted in the water stream and will visually show the GPM. GPM is derived from the pressure drop through the heat pump according to the Entering Water Temp (EWT). This is true of both pressurized and non-pressurized systems. All of the needed information is in the Spec Guide and the Owners manual.

Page 16 of the Design Guide...

Performance Data-HT036_Full Load(2nd Stage)
9 GPM = 5.2 PSI @1080 CFM Heat of Extraction = 30,800 Btu's @ 1250 CFM HE = 31,700 Btu's

Page 35 of the Owners Manual...

Unit Operating Conditions (the HT036 chart)
50* EWT @ 3 GPM/ ton Water side Delta T 6.4*~8.4* Air side Delta T 24*~30*

This is the information your service tech needs to be looking at and showing you. If he doesn't know where, or what, this information is... Time for someone that does!

Bergy