Replace Heliocol Vs new Heat Pump in Arizona

[CyprusCorner]

Hello everyone,
Long time lurker, but finally created an account as I need to make some expensive decisions soon and would love some input.

TLR
Thinking of replacing my heliocol with poor sun placement with a heat pump as the replacement and running costs of the heat pump appear to be way less than those of solar. Read on for the full story.

Backstory:
I moved into my house 8 years ago now and it already had heliocol panels installed. The direction they face isn't optimal IMO (30 degrees north of west...), so they're really only able to heat the pool for an extra ~2 months extra a year from Late April - June. Pool is perfect to swim in without the heaters from Late-June/July to September. However, they've started to leak (after only being 10 years old), and I've been plugging the leaking capillaries, but the time will come when I need to replace all the panels likely later this year.

Replacement:
With only 10 years of life on them, heliocol has quoted me 450 per panel (for just the panel itself), or 600 per panel for them to replace. I have 10 total panels. So I'm looking at a replacement cost of 6K (or 4.5K if I do it myself) for something that only extends my swimming season 2 months (likely because of the terrible placement) and will only last me likely only 10 more years here in Arizona. (Side note: My old panels were terra cotta/red colored, not sure if that increases the speed at which they degrade compared to the black ones, but heliocol only sells black panels now so I would need to replace them with black). Also, if I had better roof placement, I'd like to think I could get twice as much heat out of them, or have fewer panels....

Heat Pump:
I've read that some people can get 100-140K BTU heat pumps for only about 3-4K dollars, plus installation. Which would be at least a thousand dollars likely less overall than the price to replace the heliocol. Since my pool is only 11K gallons and because I have a demand plan that reduces my electric costs to 6cents per kWh, this heat pump could heat the pool in the same April-June spring months whenever I wanted to use it for only like 2-3 dollars and a few hours of wait time. I'd imagine that it would last longer than 10 years, and I'm good at troubleshooting electrical stuff, so if minor parts break I'm comfortable servicing it myself. For quick reference, the time/price I calculated to raise my pool 5 degrees is 3.5 hours at 1.50$ (assuming a COP of 5.7 on a 140K BTU unit). So a 10 or 15 degree rise will be double/triple that, plus some extra due to extra evaporation losses at higher temperatures.

Use Case:
The wife and I might swim once a weekend in those extended spring months, but never every day. We have a baby on the way, and when she gets a few years old she'll likely want to swim in the pool more often (as I did as a kid). We do like to host events (when covid isn't everywhere), and I would love the option to use a heat pump in say... october, or may even march, where the price will be higher to heat, but at least I have the option to heat, whereas with solar I'm fixed on my time window.

I'm honestly leaning towards ripping out the solar and going with the heat pump. I realize it would be cheaper to run if I did the solar and heat pump, but the price to maintain and replace the solar every 10 or so years seems outrageous to me since I don't use my pool every day or every week. Lets say worst case, I use the heat pump every weekend that my current solar setup buys me, that comes out to (3 dollars/wkend x 8 weekends = 24 dollars per year), after 10 years, 240 dollars is less than the extra thousand or so I would spend to have the solar installed, AND I get the option to use it during times when the solar wouldn't have worked well. Is there anything else I'm missing for consideration, this seems like a no brainer to me to switch to a heat pump! Is it safe to assume with some minor part replacement, i can get a heat pump system to last me 15-20 years? Anyone else in phoenix have bad luck with heliocol only lasting 10 years?

Thank you for taking the time to read and share (even some) input!

 

[chiefwej]

My understanding is that heat pumps are much more efficient and effective in humid climates. I have a solar system, but I don’t use it to extend the season, mostly just maintaining a desired water temp. Once air temperature drops to a certain level, we have less desire to swim. Gas heater work better for quick warming, heat pumps for maintaining a temps.

 

[Newdude]

Once air temperature drops to a certain level, we have less desire to swim.

This is exactly the inherent problem with heat pumps. The overall weather cools off and the swimming desire goes with it for the most partWeek 2 or 3 after that gets a warm surge and the desire increases, but the water is already long cold and the heat pump will need a day or more to get to a desirable temperature because even though the days warmed up, the nights are still cooler.

The fact of the matter is that gas heaters have 3X the BTUs and therefore can help more often than not when you decide that you want to swim this weekend, have a birthday party, or just because it’s a little warmer out on a Tuesday. You won’t need the weather to cooperate nearly as much as you would with a heat pump.

Many times the availability or cost of gas pushes people to a heat pump and it’s certainly better than nothing, but you have to go in knowing it’s limitations so there is less disappointment when it doesn’t perform like you’ve hoped.

Solar, like the heat pump, really excels during the warm season but may not be able to overcome the cooler months either.

 

[CyprusCorner]

Thank you for the replies so far. Like Chief mentioned, once the air temperature drops below 90 (it's a dry 90), then I don't have a desire to swim, but that doesn't happen until November - Feb here in Arizona. I discovered this when I first moved into the house, as the previous owner also had a pool blanket. With the blanket and panels, I Was able to get a warm pool in March, but it was still somewhat cold getting out of the pool, so I imagine I'll never want to get out if I could in Feb!

Additionally, I tried running the numbers for a gas system (don't have a natural gas, so I'd have to go with propane), and while the initial cost of install is even cheaper, the price to heat the pool skyrockets by almost a factor of 10 (it would be 13 dollars of propane for every 5 degree rise). That's just accounting for the price of propane, and not the extra hassle I'd have to deal with switching/refilling tanks regularly This is ultimately why the heat pump sounded so appealing.

 

[Newdude]

the price to heat the pool skyrockets by almost a factor of 10 (it would be 13 dollars of propane for every 5 degree rise). That's just accounting for the price of propane, and not the extra hassle I'd have to deal with switching/refilling tanks regularly

You would get a large tank and schedule deliveries as needed. Buying in bulk brings the cost down over filling a small tank meant for your grill. And I’m with you on the cost, the #s can be huge. But if it’s only when you want to, you’d gladly spend $75 to have a late season or even winter pool party. Or as a nice treat on a random winter weekend.

The more economical heat pump option is better on the cost of usage, but go in with your eyes open that it may not do the job at the times you want it to work. There are plenty of times it will do the job, you’ll just be somewhat dependent on the weather cooperating.

Keep us posted.

 

[chiefwej]

FIY: According to another member of the forum and lives in Gilbert, a heat pump will not even operate (in Arizonas dry air) below 55°.