I've had my contractor out here doing some work on my Climatemaster TT27 4 ton close loop unit. Anyway, it's all up and running again, and I'm trying to gauge the efficiency of the unit. I'm trying to figure out he Heat of Extraction/Heat of Rejection calculation and I'm a little confused. Here's what I've got so far... These calculations are all done with the thermostat set at 69 and the outside temp out 44, with the unit running in stage 1. EWT - 41.7 degrees F LWT - 37.4 degrees F EWP - 38 psi LWP - 32 psi Return Air Temp - 65.8 degrees F Supply Air Temp - 89 degrees F What would my GPM be??? I can't seem to figure it for what Climatemaster shows in the their manual. Can anyone help me out?

I have a geomax 2 4 ton closed. Geomax is a rebranded climate master.

My lookup table at the 40F loop temp only shows up to a pressure delta of 4.25 psi, which correlates to about 12 gpm. Your pressure drop is 6 psi (38-32) @ 40F.

Charting the pressure drop vs gpm and extending the curve yields 6 psi equivalent to about 14 or 15 gpm at 40F.

15 GPM * 8.333 * (41.7-37.4)*60 = 32,250 BtuH HE...seems OK, but you may be pumping harder than necessary.