Extracting 4 degrees from 12 GPM works out to a Heat Extracted of 24 kBtuh.

Add another 8 kBtuh for a compressor on the system running at a COP of 4-ish (may be high) and that yields a heat capacity of 32 kBtuh

That seems a bit low for an 049 with EWT in the 30s, (I'm away from my spec tables, so that guess may not survive a fact check) but it doesn't take much in the way of flow or delta-T inaccuracy to account for the difference.

Next bit of handy data would be compressor amps, but that takes a meter not typically lying around the house.

I just started one up yesterday, specs say heat extraction is 20300 BTU/H in 1stage, and 28000 in 2nd. Your numbers are more than 10% off, chances are there is something wrong with your refrigerant cycle, have it checked out. Most likely not enough refrigerant, or an issue with the compressor. Make sure your measurements are accurate.

Thanks for the help.

I do not think my measurements are real accurate, I'm using a 100psi pump pressure gauge with a ball inflator needle. Markings on the gauge are in 2psi increments.

As accurate as I can see, PSI drop is 5psi, Climate Master book goes up to 4.5 psi. Say I had maybe 13 or 13.5 GPM I'd be up to 27000 btu. EWT and LWT are measured with a digital meat thermometer, measurements do jump around a little.

Thanks again for all the help.

John

Readings from the gauge you describe aren't accurate enough to support my earlier hypothesis that heat extracted is a bit low, so I retract that.

Was testing the EWT and LWT temps again this morning, the compressor shut down in first stage for about 5min while the fan continued running. The set point was 21c and actual temp was 20c.
EWT was 34.2 and LWT was 31.1.

Is it normal for the compressor to shut off for a few minutes like this or should I be concerned?

Thanks

John

Climatemaster does that, shutting down the compressor every 4 hours for about 5 min. Anybody here who could explain why?

Thanks Doc! I guess the installer will be finding this out.

Well I had the installer out today and he did not know why, he was going to call Next Energy.

So I have some new numbers from the installer. The installer said that he took the CFM down half a notch, he was not happy with the Delta T.

Water Temp In- 33.6 Out - 28.8
Pressure In- 40 Out- 35
Air In- 64.7 Out-88.6 (This is higher after his change)
DSH In- 75.7 Out- 83.9

Compressor Amps 11.4
Ventilator Amps 2.0
Total Amps 16.0

The installers temp on Water is the only difference from my measurements, his probe goes directly into the water, where i have just been inserting my thermometer into the first little brass section, I don't think my probe will fit right in.

Thanks again for everyone that helps me out to understand how the system is supposed to work.

John

looks much better...

Posted By docjenser on 08 Feb 2011 11:49 AM
Climatemaster does that, shutting down the compressor every 4 hours for about 5 min. Anybody here who could explain why?

I always presumed it to be an automatic lockout reset.
j

Welded contactor sensor?

WF posts a warning to comfort alert after 18 hours continuous run time but does not dump the compressor every 4 hours.

I wonder what the reasoning is to subject a unit to a stop / start cycle halfway through a cold night and again the following morning?

Posted By joe.ami on 09 Feb 2011 06:44 AM

Posted By docjenser on 08 Feb 2011 11:49 AM
Climatemaster does that, shutting down the compressor every 4 hours for about 5 min. Anybody here who could explain why?

I always presumed it to be an automatic lockout reset.
j

I think it just disengages the compressor, but it does not reset the circuit board.So any fault code would still be there. Still scratching my head.