Hi, Installed a digital thermostat, replacing a manual one. The fan worked for a short time, then switched to heat mode and it didn't work. Found I had it wired one wire wrong, Wired it right, then nothing, Could this cause damage to my unit? I put the old one back on it still doesn't work. I have a heat pump and bought a ritetemp thermostat 6020.

Could this cause damage to my unit?
Most probably the incorrect installation destroyed the new thermostat. Just replace it again. Properly this time...

:)

Check for a blown fuse on the indoor unit circuit board. Also check to see if you still have 24 volt control voltage.

The RiteTemp Support Site - 6020 Technical Support Page (http://www.ritetemp-thermostats.com/6020.html) please vist this site and probably it can solve the problem

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