I had no idea it was that simple! How do you control heat pumps? I know they have a setting where if outside is too cold it runs backup electric or gas.
Heat pumps are an entirely different story, and I don’t have too much experience with them, most of the splits I’ve seen come with their own remote controls. I was talking on more traditional wall heaters, central air/furnace/forced air, etc.
Heat pumps are not simple at all. They are extremely efficient but can’t produce a large temperature gradient so they need to run very long cycles (potentially remaining on 24 hours straight). Modern cold weather air source heat pumps also tend to have variable output (variable speed compressor, variable speed fan). This demands a more complicated thermostat that adjusts the heat pump up and down, possibly with PWM.
And then there’s the emergency/auxiliary heating from the furnace. The thermostat needs to have some intelligent logic to decide when the heating demand exceeds the capacity of the heat pump and call for the furnace.
If its a cheap crappy one, the compressor is on/off depending on temperature. Decent ones will have a VFD to manage the load of the compressor so it doesn’t have to turn on/off all the time but just regulates the compressor load to match heating/cooling requirement. Both have their own controls, and you generally shouldn’t mess with them.
I had no idea it was that simple! How do you control heat pumps? I know they have a setting where if outside is too cold it runs backup electric or gas.
Heat pumps are an entirely different story, and I don’t have too much experience with them, most of the splits I’ve seen come with their own remote controls. I was talking on more traditional wall heaters, central air/furnace/forced air, etc.
Heat pumps are not simple at all. They are extremely efficient but can’t produce a large temperature gradient so they need to run very long cycles (potentially remaining on 24 hours straight). Modern cold weather air source heat pumps also tend to have variable output (variable speed compressor, variable speed fan). This demands a more complicated thermostat that adjusts the heat pump up and down, possibly with PWM.
And then there’s the emergency/auxiliary heating from the furnace. The thermostat needs to have some intelligent logic to decide when the heating demand exceeds the capacity of the heat pump and call for the furnace.
If its a cheap crappy one, the compressor is on/off depending on temperature. Decent ones will have a VFD to manage the load of the compressor so it doesn’t have to turn on/off all the time but just regulates the compressor load to match heating/cooling requirement. Both have their own controls, and you generally shouldn’t mess with them.
They have their own microcontrollers usually to manage that stuff, including defrosting