Is water flowing?

[RonL1]

I just had my HWG's re piped in from the advice learned here. I now pull from the bottom of the tank and teed into the cold in on the tank where the domestic cold house water is. Is there anyway to see if water is flowing in the pipes for the HWG's? The circuits were bled and the circulators have power, but I would like to know if the water is accually circulating since the temperature difference is so small.

[tecman]

Short of piping in a flow meter, the best way is by temperature differential. Remember with a GS heat pump, the amount of domestic HW in the summer is small. The HWG works by "desuperheating" the refrigerant. This is the heat of compression, as produced by the compressor. In the summer, the relatively cool geo water means that the heat pump does not do much work. If the water is 70 and you get 60 deg air, the heat pump is only producing a 10 deg differential. This means a low compressor head pressure, about 120 PSI, and not much heat to remove. Much higher amounts of DHW are normally available during the heating season.

paul

[RonL1]

Thanks, that make sense since my unit's are not even running much at all, and mainly in 1st stage only. My water coming in open well is always around 57 degrees.

[mknox]

as far as my experience goes, most of the newer geothermal hps that ive installed/serviced have a dedicated dhw mode. actually on hydroheat and waterfurnaces it runs before 1st stge heating and cooling. its not untill the tstat calls for 2nd stage that they stop the dhw cycle.

[geno54]

Short of piping in a flow meter, the best way is by temperature differential. Remember with a GS heat pump, the amount of domestic HW in the summer is small. The HWG works by "desuperheating" the refrigerant. This is the heat of compression, as produced by the compressor. In the summer, the relatively cool geo water means that the heat pump does not do much work. If the water is 70 and you get 60 deg air, the heat pump is only producing a 10 deg differential. This means a low compressor head pressure, about 120 PSI, and not much heat to remove. Much higher amounts of DHW are normally available during the heating season.

paul

Maybe I'm missing something
I would have thought that the summer months would be better for the DHW even at 57 deg WW than the winter months. In the winter you would want to all the heat going into the air and very little going into the water.