For the last 3 years I have been trying to diagnose why my WaterFurnace decides to stop working correctly. Cold air stops blowing from vents and is replaced by slightly blowing and slightly cool air. Once I turn the thermostat to "off" and wait a few minutes and flip it back to "cool" everything returns to normal. The only unusual thing that my serviceman can tell me is that the temperature of the water in the lines going out is 115 degrees and when it returns it is 110 degrees. He says pressures are fine but the compressor gets too hot to touch. He has contacted Enertech, which is located here in my town, and they think it is the compressor. The system has worked perfectly for 3 days straight. Last month I was turning the thermostat off/on maybe 3-4 times a day. Last winter it worked fine. I think I only had to reset thermostat twice. Got any ideas?
Yes Modern WF Envision units can take water coming in at 120 F (EWT), but it is far from ideal - efficiency and capacity suffer greatly. A 22 year old machine may not be designed for the 110 EWT you are experiencing.Has it always been so high or is it a result of the long heat wave still underway? I'm not suprised the compressor is too hot to touch Unless you are in the desert southwest, a conventional air source heat pump would likely be more efficient than a geo unit with 110 EWT. I also figure that durability and reliability will be harmed by such high EWT. Is it possible that part of your ground loop is air locked or otherwise not participating in heat exchange? It is also possible that scale has built up, further increasing refrigerant temps and pressures. A tech able to fog a mirror should be able to measure current and compare it with nameplate FLA / RLA (Full or Running Load Amps)...has yours?
The Waterfurnace WS or WX units are rated to 110F EWT @ 3 GPM per ton assuming you are pumping that much. I would give it a break if you can replacing a compressor in a 22 year old unit may not be a wise decision given the new units efficiency increase. If you have a horizontal loop you can try to soak it with water. Good part is if you have DSH you will get all the free hot water you need as marketing advertises.
I suspect the correct title of the thread should be 22year old ground loop needs diagnosis. Kelly, 1988 is among the hottest summers in my experience in this biz. How did your brand new unit perform then? What were the EWT's then. You may be marginally looped in which case you may only have trouble on extremely hot years. As they only happen about 1 in ten, you may not need to do anything, but tough it out. A $350 free standing big box A/C could make a great aux cooler. If you are seeing a trend of progressively worse performance, it may be time for a change. Good Luck, Joe
Thank you for your replies! I am going to give all of your suggestions/ideas to my serviceman. Since I posted, the unit has been working perfectly! Interestingly the outside temperature has dropped to the high 80's. If you think of anything else, let me know.
