Heat Pump for AGP - Size and cost to operate

[Gpalmer13]

Hey Folks,

I'm thinking about installing a heat pump for my 18'x30' 11k gal pool. I'd prefer heat pump vs other options for the convenience of "set it and forget it" operation with young kids that will have unpredictable usage habits. My biggest questions are

1. What size pump do I need? Talking to the guy at the pool store (where they only carry a 50k BTU pump) he recommended 50k BTU. I'm thinking for the cooler climate of Northern NY that would be too small for my pool after looking at formulas on energy.gov regarding heat pumps, surface areas, and volumes.

2. How do I calculate daily operation cost? Is there a specific formula? Initially increasing from 65F to 80F water at 13 cents/kw (I'm guessing this cost, need to actually look it up). I think my formulas are wrong as I'm coming up with $130 for a 50k pump to get it up to temp over 24 hours which seems too high based on what I've read elsewhere. Once its up to temp, if the weather is warm, I figure maintaining temperature must be pretty inexpensive especially if I keep it covered and don't run the pump at night.

Anyway, any insight on pump size and daily operation cost would be appreciated. I realize instillation costs will be several thousand $.

Thanks!

 

[slizzio]

I can't help you with costs as I am trying to figure that out myself. 50K BTU sounds very undersized though.

 

[WardL]

I have the Jandy/Zodiac JE Heat pump, Model JE3000T with an output of 137,000 BTUs. I also have a propane heater and just recently added a solar panel system. My infinity pool is subject to relatively windy conditions which sucks a lot of heat out of the water. I have run my heat pump continuously for 12 hours and the pool did not get very warm. Sorry I don’t know the temps, but trust me, it wasn’t warm water. I wanted the HP because the propane heater is pretty expensive to run and I have excess solar power. I use the heat pump exclusively to heat my spa now. It takes about 3-4 hours of running the HP to heat the spa to 102 F. If it is in the low 50s at night, the HP won’t get the spa to 102 F. When I use the propane heater in conjunction with the HP to heat the spa it takes about 45 minutes to heat the spa. The HP consumes 6.4 kW/hr. Four hours at 6.4 kWh times your 13 cents/kW is $3.30 to heat up my spa. Sorry I don’t know the exact size of my spa, but i think it is about 1,000 gallons. Now i normally use both the HP and the propane heater to heat my spa. I live in Southern California and while it is comfortable during the day, in the 70s, it cools off at night. You will want to buy a larger HP. Good luck!

 

[splashpad]

Following for future reference!