Hello. On my Lennox G60UHV-36B-090-07, while in AC mode my furnace fan blows warm air, compressor won’t turn on. I replaced the control board (p/n 100870-01) with a new board (p/n 100870-03) … everybody who sells the board says that the two boards are identical. I turned all power off prior to replacing. I changed 1 connection at a time to ensure that all the leads were terminated identically. I also took pictures of connections prior to removing them, and verified everything was correct afterwards with the picture. I powered on unit from breaker and the board lit up like normal, but the thermostat is 100% dead. No power bring received. I double checked the terminal block several times and the wires are tight and terminated the same as previous when the thermostat worked fine. My house has two systems with 2 identical thermostats, so I brought up the tstat from the other unit and it too was dead when plugged into this unit, but it worked fine again when I returned it to the 2nd system, so I don’t think my problem is a blown tstat. Plus the t-stat is only a month old. What is going on with my dead t-stat?
Have I forgotten a step? Is there a reset I missed? Little green LED on board lights like normal, so board is getting power. Just not tstat power.
Wrong board received due to a slightly different part number that every dealer says is right?
Did I blow the board? If so, how? power was off when I swapped boards, and all wires were terminated correctly.