I need a pool heater!

[CarlD]

I did not suggest a heat pump because I assumed you wanted to use a pool in far lower temps than I would consider (unless it was an indoor pool). I totally use solar, but were I to install an active heater it would be a heat pump, just a Sean suggests.

Heat pumps got a lot of bad press when they were used incorrectly as whole-house heating systems in too-harsh environments. While a heat pump works INCREDIBLY efficiently from the mid-40's and above, they fall off in efficiency rapidly below that (Sean can probably get the exact figures). But when freezing temps hit, heat pumps fail completely and fall back on electrical resistance heating, the most expensive and inefficient means. Houses and town houses that use them in those circumstances tend to be chilly.

So heat pumps were installed in lots of town house and houses in the Northern Virginia and Maryland area around DC, where they were the WRONG system for the region--it usually gets far too cold even there for heat pumps. When we bought in that area, back in the late 80's, we specifically looked for a community being built with furnace/AC units rather than heat pumps.

I don't know why heat pumps aren't the standard throughout Florida rather than A/C. When they get those cold snaps that always seem to catch them by surprise, the heat pump would be the PERFECT solution as it is essentially a reversable A/C unit.

Yet for most pool owners, a heat pump is a marvelous solution. There's less installation, just elec, not elec & gas. They pay for themselves quickly in reduced cost of operations, and they are in their IDEAL operating range at temps most people want to swim. From 60 to 80, a heat pump's going to be super-efficient at heating your water. Even from the mid 40's through the 50's it should work well. Below that, well, if it was me, I wouldn't be swimming anyway!

Still, if you are planning on using your pool when it's in the freezing and below range, a heat pump won't work and you'll need to go to gas heat. But still, I think for that an enclosure will be necessary. It's not like a 105 deg hot tub.