How do heaters work on Portable air conditioners

Which portable air conditioner with a heater works best? They will come in two forms electric strip heater (like your toaster) or an air to air heat pump. The electric heater will use an electric heating coil to heat the air. This coil will put out about 4,000 Btu's of heat on a standard 12,000 BTU air conditioner. A 12,000 BTU of cooling air conditioner with a heat pump will put out 12,000 Btu's of heat.

The heat pump is 3 times warmer that the standard heater. This is possible because the compressor is doing all the work. How a compressor works is another story, but how a heat pump works is a quick store. All you need is a reversing valve and some check valves.

To best explain this I will use a window air conditioner. An installed window AC is mounted in a window, one side puts out cool air and the other side puts out warm air. Air conditioning 101. If you turn the AC unit around, you would have warm air in the room and cool air outside. 12,000 Btu's blowing outside means you have same amount of energy blowing warm air into the room. "Energy is never destroyed only transferred".

Back to the heat pump, by using reversing valve on the refrigeration piping inside the unit the portable AC blows cool air out its exhaust hose. The indoor unit is now a space heater, and you're cooling the back yard. This will only work when the heating operation temp is above 41F.