I've read plenty of comments on this board and elsewhere for me to decide that for a heat pump, bigger is better. The question is...at what point does it become uneconomical to get an even larger sized heat pump. For example...I used the "heat pump sizing app" on the Hayward website and it suggested for my 20,000 gal pool the 110,000 BTU pump. My guess is that if I went with that pump, it would run basically non-stop. Therefore, I should go for a larger sized heat pump that would cycle on and off and have a little extra "oompf" when needed. OK, Hayward makes 125,000 and a 140,000 BTU models. A friend, with a slightly larger pool (28,000 gal) has just installed the 140,000 BTU heater and he is as happy as a pig in mud with the way it heats his pool...without a solar blanket! With my slightly smaller pool, would I be as happy as the pig with the 125,000 unit or should I also go for the 140,000 BTU one. The price differential is minor, so that really isn't a deciding factor. I guess what I'm concerned about is whether the 140,000 unit is going to cost me more to heat the pool than the 125,000 unit. My limited supply of logic tells me that they both will cost the same, but the 140,000 unit will simply not run as long or as often. So, I should go for the larger heat pump and it will need to run for shorter periods to maintain the desired temperature. I would really appreciate any help in deciding between the 125,000 and the 140,000 BTU units.
