I have a Z Wave based Thermostat and have had several times where the Temperature scheduler app failed to trigger warming my house, so I enabled the Thermastat controller and it seemed perfect until night came and I heard it switch my A/C Compressor on to quickly cool the house off for sleep. The problem, it was below freezing outside which is VERY hard on the A/C Compressors. I ended up as a short term measure pulling power to my A/C Compressor. But is there anyway to add an override to the controller where it won't signal cooling on the thermostat, and instead just set it to a heat set-point at the chosen minimum temperature so that it doesn't prematurely break my A/C unit?
Most thermostats I have seen, including dumb mechanical types, have a mode selector switch or setting.
The 3 modes are Heat, Cool, and Auto.
If your AC turns on when reducing the set point temperature, in the winter, then you are operating in Auto mode.
You should be operating in Heat mode during the winter months. If you reduce the set temperature by even 20 degrees, it will simply allow the temperature to drop naturally until the new set point is reached, and then turn on the furnace to maintain that temperature.
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Thanks for the response.
I ended up pulling power to the AC compressor and disabling the Hubitat's Thermostat controller, going back to just basic scheduling + some rule engine rules to ensure it is in the right mode based on outside conditions e.g. if it is not too cool outside to run the compressor switch to AC mode at night and heating in the morning. But switch the thermostat to off if cold is called for and it's too cold for the compressor to safely run outside.
