We have a 15 year old premier water furnace. Mostly very trouble free. Setting the air conditioner lately to 72 and waking up in the middle of the night to find the temp has gone down to 63. The contractor put in a new 200. Dollar thermostat. Same problem occurs. Everything looks good inside, contactors, wiring etc. I am a licensed electrician and this is out of my field. I could set up some tests. Any suggestions? The hvac contractor is stumped too and the charges are adding up.
I'm a homeowner and just guessing. I wonder it this can be due to a bad relay in the WF unit that turns the unit on when it receives a call from the thermostat, but fails to turn the unit off when the thermostat is satisfied?
Thanks, gnome. I am looking for the easy way out using this forum. I haven't had any real problems wf/ in 15 years. The stuck relay has crossed my mind also. I have two fine fluke voltmeters and can set them up for lnterval logging. Thinking about setting them on stage1 and stage two of the thermostat. Trouble now is cooler weather. Air conditioner won't get a good workout. Crazy, but i guess i could fire up the wood stove.I suspect heating will be a problem too. Might even be the mother- board. Problem is intermittent.
Thermostat wiring Possible reversing valve fault. Unit thinks it is heating and will never achieve the temperature. This is usually a thermostat programming issue.
