we have a Nest learning 2nd generation unit
it has been working fine for both AC and heat; it is using 4 wires Y1, G, W1, and Rh
the AC Fan on demand comes on but the compressor does not
if I remove the Nest and connect the Red to the Yellow wires the AC system runs fine
my HVAC repair man is saying that we need a new thermostat....
how do I test the Nest that it is working properly?
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