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View Full Version : Heater pros and cons



stosh507
04-20-2006, 09:45 PM
It's getting down to the wire. I need to make a decision on a heater. I have all 3 of the major ones on my mind (propane, heat pump, and solar), but I would love some more input from experienced users. This is my first post, but I've been watching for 3 seasons now. The first thing I need to say is THANKS! Ben and this forum taught me pool chemistry and it's such a breeze once you understand everything that's going on. I love asking pool dealers advice on chemistry and just laughing to myself about what some of them say. Also, members on this forum convinced me to go with a SWG chlorinator which I absolutely LOVE.

Here are some details first: I live in PA (between Philly and Harrisburg)
Autopilot SWG
DE filter, 1.5HP single speed pump
30,000 gal IG pool, vinyl liner, "L" shaped
shallow end gets 85% of the day full sun
deep end gets 70% of the day full sun

Here's what's eating me up:
Propane pros:
fast heat, fast heat, fast heat - also reasonable startup price even with buying a tank and filling it.

Propane cons:
expensive fuel, dangerous fuel, ugly fuel storage, slight inconvenience to get tank filled, also I hear maintenence is high on these things.

Heat pump pros:
less expensive to run, convenience and neatness of operation and location.

Heat pump cons:
100,000 BTU is SLOW, would have to run pump 24/7 (at least in spring and fall) instead of the 5-6 hours it runs now. Purchase price is high

Solar pros:
least expensive to run

Solar cons:
real estate loss, asthetics, not having an optimum location, medium expensive setup price, no heat during a hurricane! (or cloudy days)


I have 3/4 acres, so solar would probably be a pretty high choice on the list IF it wasn't so hard to locate. I have a few great spots like on top of my house (south facing roof), but that's 25' in the air and about 100' away from the pump. That's a long run for a bunch of panels in series - not very efficient. Another great spot would be between the house and pool, but my wife and I don't want to look at them every day outisde our windows. Behind the pool area would be perfect if it weren't shaded about 40% of the time (it's close to a tree line so full sun from about 11:00 on).

Many people are raving about heat pumps, but I have some concerns. I see that the cost to run can be 50% or better than propane. But what if I only used the propane on Friday night to heat for the weekend? If I only use a 50% efficient heater 33% of the time, am I really saving anything? It looks like I'd have to run the heat pump 24/7 in the spring and fall, right? This would increase the cost to run because the pump would have to run for the heat pump to work. Also, the huge selling price and knowing I'd have to run another electric service out to the pool doesn't really excite me either. I ran the first service myself to save money. It's a 55 amp service, 220V. My SWG and pump both run on 220, so amps are small. The pump runs on 20 amp breakers and the SWG on 10s. I think their actual usage is around 23-24 amps total. That leaves 30 amps. How much do the heat pumps guzzle? Would I actually have to run another service?

My friend has a propane heater and he complains about it. He says it breaks down every few years and he hates calling for propane. The tanks are ugly too. But you got to admit, 400,000 BTUs sure sounds warm and snuggly.

Is there anything I missed here? I'd love to hear from people in the mid-atlantic or northeast with heat pumps find out what their bills are AND if the heat pump can actually keep up. Also, can solar panes keep up without a backup heat source? How many panels would I need for my 30,000 gallons with about 60% full sun? I'd like to heat to about 80 (me) to 85 (wife) degrees. Sorry for the long post. Thanks in advance.

Stosh

cleancloths
04-21-2006, 10:28 AM
I have a 30,000 gallon IG pool in NJ with a heatpump that is sized at 85,000 BTU/Hr and it works great. I have had it for quite a few years and have never had to do any maintenance on it. It will raise the temperature about one degree every three hours -- not as fast as a 400Kbth/hr gas heater but fast enough. Once you have the pool up to temperature the unit does not have to run much to maintain temp if you have a solar cover on the pool when not in use. Check some of the mfg pages as far as breaker sizing and amperage draw. If you are close on your electrical, or if you want to trade-off capital versus operating costs get one with the highest COP you can find. COP = coefficient of performance and tells you how much heat energy you get out for each unit of energy you put in.

If I had it to do all over again I would go with the heatpump rather than solar due to the large amount of surface area you need for solar. I believe you need roughly the same square footage as the surface area of your pool to be really effective. As far as putting on the roof, thanks but no thanks the damage the could take place in event of a leak would never be worth that risk in my mind.

stosh507
04-21-2006, 11:16 AM
cleancloths,
Thanks for the response. Sorry for my ignorance, but specifically what risk of damage from a leak are you talking about?
I will definitely have to use the solar cover like you say. Sounds like you are very happy with the heat pump.