On 11/2/2010 8:32 AM, willshak wrote:
JimT wrote the following:
This is the first year I've been able to use my pool heater in the
fall because I got a heater earlier this year (266k BTU Rakpak Nat
Gas) capable of heating the pool in a reasonable amount of time. I
plan to use it into December if the weather holds out.

The pool is an outdoor, in-ground, 10.5k gal pool. I'm in Central Tx.

I've been kicking the heater on about 5pm to go swimming about 8-9pm.
I keep it anywhere between 83 - 87F.

Is it best to leave the heater on all the time or shut it down until I
want to go swimming like I have been?

Jim

I seem to remember that many years ago, my then FIL had a pool heater
(250,000 BTU) for his above ground oval pool. It took about 1 hour to
raise the water temp 1 degree.
Does that sound right now?

It take 1 BTU to raise 1 pound of water 1 degree F. So for a 30K
gallon pool, that would be right. Not counting losses which can be
appreciable.

Jeff