The Homemade Heat Pump Manifesto

randen · 04-04-12, 09:39 PM

The GSHP has been operating 24/7 for about 3 weeks. With the outside air temps around -5 Deg C up to 2 Deg C. during the day and no sun the shop temps stayed at 19 deg C. I had to watch the evaporator for icing up as its on the ragged edge with no anti-freeze and the loop temp at 6 Deg C. The high side was sitting at 250psi and the temp out from the condensor was 28 Deg C. Today I had some time to experiment. I had seen that the ground loop temp had actually risen to 8 Deg C so I increase the pressure to 290 psi HS and the condensor out was 38 Deg C. and the evaporator showed no sign of freezing up. The shop temp popped up to 26 Deg.C. What a difference the extra 2 Deg.s in the loop temp. makes. As Vlad had pointed out I have to make some changes to get balance. When the threat of cold weather is over and time allows I think a larger evaporator and anti-freeze.

Thanks Guys
Randen

04-04-12, 09:39 PM	#11
randen Uber EcoRenovator Join Date: Apr 2011 Location: Strathroy Ontario Canada Posts: 657 Thanks: 9 Thanked 191 Times in 129 Posts	Home Made GSHP 3.5 ton The GSHP has been operating 24/7 for about 3 weeks. With the outside air temps around -5 Deg C up to 2 Deg C. during the day and no sun the shop temps stayed at 19 deg C. I had to watch the evaporator for icing up as its on the ragged edge with no anti-freeze and the loop temp at 6 Deg C. The high side was sitting at 250psi and the temp out from the condensor was 28 Deg C. Today I had some time to experiment. I had seen that the ground loop temp had actually risen to 8 Deg C so I increase the pressure to 290 psi HS and the condensor out was 38 Deg C. and the evaporator showed no sign of freezing up. The shop temp popped up to 26 Deg.C. What a difference the extra 2 Deg.s in the loop temp. makes. As Vlad had pointed out I have to make some changes to get balance. When the threat of cold weather is over and time allows I think a larger evaporator and anti-freeze. Thanks Guys Randen