New indoor pool - what kind of heating?

[Rbrenton]

Is a heat pump the same thing as a heat exchanger? I'm not sure how these work.

[cleancloths]

You can think of a heatpump as a central airconditioner running in reverse. An airconditioner absorbs heat from the room and dumps it outside, hence cooling the room. A heat pump absorbs heat from the outside air and dumps it into the pool, thereby heating the pool. They typically have a COP of about 5-6 which means for each unit of electricity you put in you get 5 to 6 units of heat out. Much more economical than gas or propane heat.