New Pool, Heater Help/Advice

[aumfc]

My new in ground pool was finished recently and we were given the green light to turn on the heater.

The pool is 35,000 gallons with 1,000sf surface area according to the build specs.

We are using propane and opted for a heat pump heater/chiller. I was lead to believe that while slower to heat, it would still be sufficient to get us an extra couple of months in the pool.

I'm in central AL, so I was hoping for pool use 9 months of the year.

The heater is 140,000 BTU.

I turned it on at 3pm yesterday when the pool water read 73 degrees. As of 8am this morning, it's reading 74 degrees.

The temperature bounced between 73 and 74, so I'm not even sure the heater was doing anything.

Is it really going to take running this thing 15+ hours to raise the temp 1 degree? Or, is my heater not working as it should?

What other information do you need to factor in?

Thanks.

 

[ajw22]

Do you have a cover on the pool?

 

[aumfc]

Do you have a cover on the pool?

No.

 

[ajw22]

No.

That may be part of your problem.

Your 140K heater can heat your 35K pool a maximum of 1/2 degree per hour. And that is when air temperature is 80F with 80% humidity which you don't have at night. So the HP may be heating only around 1/4 degree an hour at night temperatures.

Depending on your nighttime temperatures your pool can lose almost that much without a cover.

With a HP you need a cover to retain the heat you are spending money creating.

 

[ajw22]

We are using propane and opted for a heat pump heater/chiller.

BTW, your HP runs on electricity and has no connection with your propane.

 

[SJPoe]

Rough napkin math says if you don't have a cover, you're going to be barely heating at all...
Heat Loss = 1000sqft x 5BTU/hr x Diff in temp in F ) Looks like your difference was roughly 15F last night) = 75,000 BTU/hr.Leaves you 65000 BTU for heating
30000 gallons = 250000 lbs. 1BTU raise 1Lb by 1F per hour...
250000 / 65000 = 3.8 hours to raise it by 1F = roughly 1/4F per hour

I generally get about 1/2-1 degree/hour from my 250K BTU, but I'm dealing with much colder air temps here overnight.
Doing the same math, I should see a loss of around 650,000 BTU overnight (midnight to 7am). My actual loss was around 355000. my $200 cover saves me near 50% in heating costs...

 

[aumfc]

BTW, your HP runs on electricity and has no connection with your propane.

Right, I was just explaining that we are on propane so opted for an electric heat pump (I know that's redundant) since we only have the stove running on LP, and don't have a large tank.

 

[aumfc]

Thanks all.

My pool is a free-form pool 43'x35' feet. It's basically 3 large circles in an L shape.

Anyone know a good place to get a cover for something like that?

Starting to feel like I just wasted a lot of money on a heater that's not going to work for me.

 

[SJPoe]

Starting to feel like I just wasted a lot of money on a heater that's not going to work for me.

Once you have a cover on, you'll probably see a slow, but steady temp increase. Once you get to temp, you're only dealing with replacing the heat loss, not trying to heat the body of water as well.
Trust me, my gas bill in April makes me cry...but then my Wife and Grandson's enjoyment of the pool makes it all worthwhile.

 

[Rancho Cost-a-Lotta]

My pool is a free-form pool 43'x35' feet. It's basically 3 large circles in an L shape.

I'm on my third year with the Sun2Solar 1200 series. Still holding up.

Sun2Solar®Supreme Blue Solar Cover 20\' x 45\' Rectangular 1200 Series™ - SolarCovers.com

Sun2Solar® Supreme Blue Solar Cover - 1200 Series™ | 20 x 45 Rectangular Solar Covers | SolarCovers.com

www.solarcovers.com

Covers come in rectangle or circle shapes. You trim to fit your pool. You'll need to figure out the best way to cut the cover to fit. With a large pool like yours, you may need to cut into sections. I cut mine into two larger sections and used scrap to fit the smaller section. I can remove and install the cover on my own. I fold the sections, then roll them up into 5' wide rolls. Here's what it looks like...

 

[shaded_water01]

There are also liquid solar covers. I've had success with them, but they are a frowned upon option here.

 

[aumfc]

I'm on my third year with the Sun2Solar 1200 series. Still holding up.

Sun2Solar®Supreme Blue Solar Cover 20\' x 45\' Rectangular 1200 Series™ - SolarCovers.com

Sun2Solar® Supreme Blue Solar Cover - 1200 Series™ | 20 x 45 Rectangular Solar Covers | SolarCovers.com

www.solarcovers.com

Covers come in rectangle or circle shapes. You trim to fit your pool. You'll need to figure out the best way to cut the cover to fit. With a large pool like yours, you may need to cut into sections. I cut mine into two larger sections and used scrap to fit the smaller section. I can remove and install the cover on my own. I fold the sections, then roll them up into 5' wide rolls. Here's what it looks like...

View attachment 488773

This sounds promising to me. Can you tell me more about this? How do you take it on and off? Do you have any photos of that process or even photos of how you store the cover? How often do you cover / uncover? When do you run your heater?

Thanks for the advice.

 

[Rancho Cost-a-Lotta]

Do you have any photos of that process or even photos of how you store the cover?

Here is an old post that shows the process. I have a good amount of deck space to work with. When removing the cover, I rinse each section, then fold and roll. I then tie each roll with nylon rope using different colors so I know where it goes. I don't have photos of the sections rolled up.

Just cut solar cover to fit!

I just cut my 25x45 solar cover to size and installed it. I am doing a test and running my heater until 9:00pm tonight, turning it off, and seeing how much heat I lose by tomorrow morning. I'll post results back here! Temp when I turned on the heater was 55. Low tonight is supposed to be 41...

www.troublefreepool.com

How often do you cover / uncover? When do you run your heater?

I never cover the pool off-season. We don't close the pool.

During the shoulder months, the pool generally stays covered all week except while we're swimming. At least once a week I will uncover the pool for maintenance. I only run the heater when the pool temp needs a bump. It's been unseasonable cold, so water temp is down to 76 now. I'll bump that up to 84 before we swim again. That's about 3-4 hours of heater runtime for me.

During the peak summer months, the cover is not needed.

 

[Rancho Cost-a-Lotta]

This sounds promising to me. Can you tell me more about this? How do you take it on and off? Do you have any photos of that process or even photos of how you store the cover? How often do you cover / uncover? When do you run your heater?

Thanks for the advice.

I took a few pics of the process this morning...