Heat Pump Question

[Diverdavis]

Hello,

I have a fairly large pool (36000gal) and I'm thinking of adding a heat pump. I'm limited to 40 amps without upgrading my electrical systems. Is there any harm in under-sizing a heat pump besides it just taking long to heat the water? I'm in Ontario and only really need it in May to get it up to temp and its stays in the high 80s all summer long on it's own.

 

[ajw22]

What is your air temperature range in May? HP output reduces as the air temp decreases and stops operating at 50F.

With 40Amps you are limited to a 75,000 BTU heater that may only put out 50,000 BTUs at 50F air temp. You have almost 300,000 lbs of water and 75,000 BTUs will heat the water 1/4 degree an hour.

To even possibly make it work you need to have a pool cover to prevent heat loss from evaporation. And even then I doubt it will do much when you can get less then 6 degrees of heat in 24 hours of running from the HP.

Heat Pump Performance

• ajw22
• Feb 23, 2019

Pentair Ultratemp Heat Pump BTU Output by OAT

 

[Diverdavis]

Thanks! In May we can get temps between 50F to 80F (65F avg) during the day. I do have a solar cover. I'm good with 6 degrees per day. My daughter has a birthday June 3rd so I just want it warm by then. Sounds like I can just fire it up 3 or 4 days before I need it warm and I'll be good to go.

 

[Diverdavis]

I checked my logs from last year and the water was 71F on June 2nd with no heater. Just a little to cold for a party... Even adding 7 degrees would make it okay

 

[ajw22]

I assume you have inexpensive electricity.

 

[Diverdavis]

Yep. I have some onsite solar with no time of day rates so it's only 12 cent per Kwh