I have a Totaline thermost model P474-0100 which controls a NORDYNE heat pump model P3RC-042K. I went away for a few weeks and when I returned the Totaline thermostat will not work.
I am trying to see if the problem is the thermostat or something else. The LCD on the thermostat is blank, not lit. The light on the thermostat is not lit. I measure 28 volts on the thermostat between the R terminal (24v hot) and the C terminal (24v common). Does this sound like the problem is the thermostat? What else could I measure to prove or disprove where the problem is?
Thanks so much in advance.
Just joined the board. I have a Totaline P474-1100F Wireless Programmable Digital Thermostat. I have two stand-alone thermostats, and one unit on the wall hardwired. That unit has four LEDS, Heat, Cool, Fan and Power. Normally the Power is lit, but now all are dark. Breakers are all normal. I live in Phoenix...108F so it sucks not having the A/C. Any ideas....perhaps a reset of any or all of the unit? Seems the two T.S. are not talking to the wall unit...