Need a new pool heater....

[EmmaApp]

So, I'm discovering that pool heaters are like learning the pool chemistry (which I'm pretty darn good at now - if I do say so myself!)

Please guide me in the right direction so I have somewhere to start!

In Houston TX, 25,000 gal saltwater inground pool with spa. We currently have a Jandy something-or-other heater that I'm not convinced has worked in years (we bought the house in May) and I can turn it on but the display has melted and it turns off again within minutes. Everything is plumbed for gas already. I'm not sure what HP pump we have.... but can find out if I need to.

Having never owned a pool, we have very quickly come to rely on the therapeutic properties of swimming in your own pool!

questions:
1. Good brands?
2. BTU?
3. Buy from a company who will install? Or buy from manufacturer (or online) and get installed by licensed person/company.
4. Approximate operating costs...? I know all pools are different, but maybe someone else in the southern States can give me an idea.
5. What is a normal/usual cost to purchase and install?
6. Any questions I should be asking (please include answers)

Thanking you all in anticipation of your wise words and every little bit of input.

 

[Catanzaro]

Emma:

Considering you have a gas line, it would be best to go with a gas heater. Personally, I have a heat pump, but you would be better off swapping out a heater. It probably would be best to have a professional install the unit. If you search the forum, you will find a lot of information on natural gas heaters. Most gas heaters are within the same specifications regarding efficiency.

The units will cost money to run, bottom line. There are too many variables to consider to determine how much the true cost of running a heater will be. Maybe other members will chime in and give you experience in Texas. The bottom line is that sometimes without a heater, the pool will not be used. Understand that the cost of running a heater may run a few hundred dollars per month.

 

[Hammond]

Agree with comments above about getting a gas heater. You need to think about how much you want to run it. In my experience it takes a long time to heat a good size pool like yours if you are starting out with cold water. OTOH a good size heater will warm your spa quickly and in Tx with low gas prices it doesn't cost much to run the heater to warm the spa a couple of times a week

 

[ps0303]

Having never owned a pool, we have very quickly come to rely on the therapeutic properties of swimming in your own pool!

questions:
1. Good brands? Raypak/Rheem
2. BTU? If you were happy with the size you have now, get the same or close to it. Raypak has a 266K and a 400K BTU units. Gas line size will also matter if you don't have a 400K unit now.
3. Buy from a company who will install? Or buy from manufacturer (or online) and get installed by licensed person/company. If you buy online and don't have installed by a licensed company, the manufacturer will most likely not honor the warranty.
4. Approximate operating costs...? I know all pools are different, but maybe someone else in the southern States can give me an idea. I can't say about your area on operating cost. Get a solar cover to help keep the warm water warm during the cooler months.
5. What is a normal/usual cost to purchase and install?This will vary based upon your area. Definitely over $2k for sure though.
6. Any questions I should be asking (please include answers)If you do NOT currently have a 400K BTU unit but want that size in your new heater, you will need to verify that your current gas meter/line will support it.

Thanking you all in anticipation of your wise words and every little bit of input.

Answers in red.

 

[Swampwoman]

Emma, Paul has you covered, but here's info to give you an idea re calculate operating cost.

So, I'm in Michigan, totally different climate than you. Because I have a house boiler etc., the Raypak 266k btu unit was the biggest I could install without redoing gas lines (which run several hundred feet).

My pool is about the same size as yours (24k gal) and depending on weather temp differential, I get about 1.5 degrees per hour, sometimes more, when heating in normal in-season conditions.

In terms of gas cost, my NG is .77 per CCF, and with approx x 80% efficiency, my heater will use about 2 CCF (therms) per hour when heating.

So my gas bills in a normal season heating to 90+ degrees daily in a shady pool run in the $250/mo range, higher in shoulder months like May and Oct, but controllable with cover.

Last year I got an inflatable winter dome and now run all year. With temps in the 20s at night right now, I still get to 95 overnight (for am physio) with a cover in about 6 hours...during day, I'll lose about .3 degrees an hour. So even though I'm in Mich in winter, right now I'm still swimming for about $350 a month in natural gas to very high temps, and in Jan that might bump up to a high of $500.

Using a cover is very important, because 70% of heat loss is from evaporation. If it weren't for my cover there's no way I coud keep the water in the 90s in winter in Michigan

The theoretical advantage of a 400,000 btu unit over a 266,000 btu unit is that you can heat faster without as much heatloss over time. So you could likely get say 3 degrees an hour...But remember that you'd be using about 3.2-4 CCF or more an hour when doing that.

I believe there is a formula...can't recall, but it might be gallons time weight equals btu required for 1 degree. I'm pretty sure you will need at least 200,000 BTU capacity to get a degree an hour with your size pool.

This link will help you calculate scenarios. SWIMMING POOL ENERGY TEMPERATURE CALCULATOR | Neil Anderson

 

[Mayorb]

Ninety five percent of pool/spa combos in Houston area have a 400K btu heater, but make sure. The heater info should be inside the panel.
The difference between the sizes of heaters is how long it takes for the temperature to rise. A smaller heater will heat to the same temp as a larger model, but will burn less gas for a longer period than the larger model. The larger one will burn more gas for a shorter time. Comparatively, the gas used is equivalent.
Heat pumps aren't very effective here. I have only seen one, about 18 years ago, and that was a display unit at the wholesaler. It's too humid. Swamp chillers are not as effective either.
I agree with Paul, the Rheem/Raypak brand is strong, proven reliability for many models/years.