I recently purchased a Nest as a gift for my Daughter since I own 2 in my house and love it. Unfortunately, installation for them didn’t go all that well. Everything appeared to be working but then we noticed the blower doesn’t shut off even when the a/c is off.
After verifying compatibility on the Nest website and reviewing all the wiring is correct, we reinstalled the old thermostat only to discover the same problem. A problem that wasn’t there before installing the Nest.
This suggests installing the Nest somehow damaged circuitry in the a/c unit since it worked properly previously.
Now we’re attempting to troubleshoot the a/c with the original thermostat. Bottom line is the blower no longer shuts off.
The components in the unit are a control board, a 24 v transformer and what appears to be a solid state relay. Obviously, we don’t want to start replacing components randomly with no understanding of what might be damaged because of cost.
Can anyone shed light on a problem like this? Particularly some insight on what might be in the relay, but the problem over all?