[AlanJohnson]

Jeff,

I am about to pull out my old control board and do this (for my bedroom ac unit). I had a couple questions, if you don't mind. I am doing one thing different, I am not changing my thermostat. So if you don't know the answers, I understand. I checked and the old thermostat sends 12vdc signals to the AC unit.

1. Do you see any reason I can't use 20a contactors that have 12vdc coils controlled from the old bedroom t-stat? (I am assuming the coils can't use much power, and the old thermostat won't have a problem powering the coils on the contactors).
2. I think the bedroom ac unit is limited to only one compressor when the electric water heater switch is on. Did you have to deal with this? It appears this is just controlled from one of the signals sent on the same wires coming from the t-stat.
3. Someone made a comment in an earlier post, and I think it was just a typo. The compressors do NOT have two speeds, correct? The condensor fan (and evap fan too) has two speeds, but not the compressors. The compressors work with either one on, or both on, depending on what is called for from t-stat?

Thank you,
Alan Johnson