Heater Selection Help

[IL_WS]

Looking to add a heater this year (2nd year of pool life). Planning on something around 150kBTU natural gas. To be honest, I am a bit overwhelmed by options and choices. I looked through information at http://poolheaterguide.com/gas-pool-heater-reviews/. What I don't fully understand (haven't tried fully yet) is how efficiency will affect cost. Some options I am considering are Hayward universal H150 (82% eff, $1140), Jandi LXi 250 (88%, 1666), Jandy LRZe 175 (83%, $1280). All prices are from bargainpoolsupplies.com.

Several questions:

• With pH in balance, how long should I expect these heaters to last?
  Will a larger unit cost excessively more than a smaller able unit (250 vs 150)?
  bargainpoolsupplies.com seems to have must lower costs in all categories of products. Any feedback on them?
  Being in Chicago, how much should I expect to save between different efficiencies (82-88%)?

I should also add that I am not too good at navigating this site yet. I found several references to extended discussions (especially between gas and heat pump), but couldn't find them.

 

[Bama Rambler]

Gas heaters normally run between 80% and 90% efficient and the higher the better within reason. I wouldn't pay a lot to go from 80% to 82% but it may be worth a bit to go from 80% to 88%.

Another thing to consider id your location. You really should consider at least a 250k Btuh unit. I think a 150k unit will be too small on a 13,000 gallon pool in your location. I'd even consider a 400k Btuh unit.

 

[IL_WS]

I thought size was mainly driven by time to heat from cold. Following the math at http://poolheaterguide.com/what-size-he ... -you-need/, it looks like I would need 94kBTU to rise 20 degrees in 24 hours (R=12', D=4', A=7.5gal/ft^3, B=8.33lb/gal, ti=24hours, Te=20degrees >> R^2*PI*D*A*B/ti*Te). So a 150kBTU heater at 82% eff would rise 20degrees in 18.3 hours (24*94/(150*.82)). The 250kBTU heater above would rise 20degrees in 10.2hours (24*94/(250*.88)).

The difference in cost to heat from cold would be driven by the efficiency and time required to get hot. At $0.5/therm, the 150kBTU 82% unit would cost $13.73 to rise 20degrees in 18.3hours, and the 250kBTU 88% unit would cost $12.75 to rise 20degrees in 10.2hours.

I was planning on achieving a temperature and maintaining it. In this case, a bigger heater will just run much less often. I would suspect cost to be similar.

My natural tendency is to spend as little as possible on a heater since I do not expect it to last longer than 7 years. However, I don't want to make that decision if I will be sorry for it until the heater dies.

Also related to my list of items in the original post, how/where can I find discussions between gas and heat pump? Initially it seems like gas will be faster to initially heat, cost less upfront, but heat pump will be cheaper to maintain temperature, and last longer. I would love to see educated discussions on both sides. Unfortunately, many pros and cons I have seen are from biased analysis, so I cannot even trust their numbers.

 

[Bama Rambler]

If you're seriously considering keeping it heated all the time then a heat pump is probably the way to go. However, in your location it's going to cost a lot to keep an outdoor aboveground pool heated to a reasonable temp for swimming all the time.

 

[ps0303]

Being originally from IL, Plainfield, I would go with gas and not even consider a heat pump. IL just doesn't lend itself to the type of weather that a heat pump works efficiently in. As for size, I would go with at least a 250K BTU Unit. As for efficiency of a gas heater, in order for the units to be efficient, it means more parts such as blower motors etc. Which down the road means more things that can go wrong and cost you in repairs. Now if you could get an efficient gas pool heater like you can get a high efficiency gas furnace, then I would say go for it. But realistically gas pool heater efficiency is somewhat of a scam, in my opinion. So if someone told you they had a 90% efficient heater, BS!