Pool/Spa Heating gas or electric


Mar 27, 2016
Orlando fl
We are in the process of finalizing a pool contract with a spa, in Orlando. Trying to figure out if we should put a gas or electric heater in.

Big questions I have:
  1. If we put in a 400K gas heater with a 100 pound propane tank, how may hours of heating can we expect to get?
  2. What kind of a life span can we expect out a pool heater?
  3. If we use electric heater how much time can we expect it take to heat the spa?
  4. What do we need to do to ensure we can heat only the spa, or pool/spa. We will have an RS8 installed with the system.
Solar is out because pumping water onto the roof scares me and we have 40PV panels already.


Gold Supporter
May 20, 2020
Katy TX
Pool Size
Liquid Chlorine
I for one always like gas over electric. Storms rarely affect gas lines so you can always have gas such as for your stovetop or house water heater. Obviously with a pool you also need to have electric to run your pump so gas or electric pool heater is a mute point. Does your spec show which is more efficient?

Propane consumption is truly dependent on use of heater. If you only heat your spa then that will extend the time to refill propane. If you heat your pool that is a different story. My heater states it could take +12 hrs to raise temperature 30 degs for 14,000 gals.

I had a pool heater that lasted 14 years - had some maintenance occasionally but finally purchased a new one recently 400BTU.

Your heater specifications should outline how time to raise the water x degrees. For instance, my heater states it will raise the temperature 30 deg in 31 mins for a spa with 700 gals. Check your heater specifications

It is fairly standard on your return line (after the heater) that it can split to either the pool or to the spa. This is controlled by a valve and that valve can be controlled by your RS8. This is part of your standard plumbing for circulation.
On mine, when in pool mode, I have 1 jet that enters the spa to spill over into the pool So in theory I could heat both the spa and pool at the same time, however the pool has 5 returns so majority of flow is going to the pool.

Hope this helps.
  • Like
Reactions: Joshwl2003


Well-known member
Jul 20, 2020
Houston, TX
If I couldn't have gas I probably wouldn't even bother with a heater. Electric will get very expensive, a heat pump might be a better option if you have to go electric
Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.