How to either cheaply heat a pool, or heat a pool for one day?

[Poconos]

Welcome to the forum.
Sorry I don't have any solution to your problem. Believe me, if I did I would have done it myself many years ago. The things that Ben mentioned, solar cover and solar panels, do work but as he said, not guaranteed when you need it. Unfortunately a gas heater is the only device I know of that has enough BTU capacity to do what you want as fast as you want.
Al

[PoolDoc]

Thanks, Al. I knew of there was a way to do what he wanted, you'd know.

[Poconos]

Know? I didn't know.

[PoolDoc]

So, now I know that what I thought I knew before -- that there was no method -- was knowledge and not it's absence. (it's almost 2am; I need to go to bed.)

[Pete Hughes]

I had a similar situation early last year for similar reasons to you.

I did find a cheap solution which I know the "chemicals" guys are going to slam me for.
The cost was less than $30 (estimated fuel cost) for a temperature increase of 25 plus degrees in a few hours in a 6000 gallon pool.

I have multiple zones on my boiler.
I "tapped" into the laundry area zone with a regular garden hose on the drain/bleed hose bib.
I threw the hose on the ground next to the pool. I then turned up the thermostat in that area of the house to 90 degrees so that the circulator pump and demand for heat (Oil burner) was constantly running. I let it run for about 20 - 30 minutes, constantly checking with a bucket to see if the hot water coming out was clean. When it finally was, I threw it in the pool and waited 4 hours. I had to let “some” water from the lowest drain (THE COLD END) every hour or so.
By mid early afternoon, the pool had gone from 56 deg to 82 deg.

I tested the water with the Taylor kit (recommended by Ben and many others) the day before and the day after. There was little to no difference and the water seemed fine while swimming and was easily maintainable for the remainder of the season.
My pool cost less than $300 so I was not too concerned about what I might do to the liner. As it turned out, there was no apparent damage.

This is what I did. That doesn’t mean it is what you should do, just food for thought.

[PoolDoc]

Hi Pete;

I'm glad it worked for you. But, I wouldn't recommend it for ANYONE else. Here's why:

Most boilers used for home heating use recirculated water. In some cases, this water is treated with toxic chemicals, which help protect the piping, but don't hurt people . . . . because people are never in that water. In other cases, the piping & boiler are corrosion resistant, so long as not too much fresh water is added, but that water will itself become metal contaminated. And there are still other cases.

The bottom line is: if someone knows enough to KNOW that they can do what you did, without damage to their pool or heating system, then they won't need to ask how to do it here. But, if they do ask, we have to assume that they do NOT know, and don't have the skill to determine whether they can, or not.

There are many things I've done on pools and with pool equipment that I'd never mention here, because they are "don't try this at home, unless you are an expert" sort of things.

What you've suggested worked well, and economically, for you. That doesn't mean it's appropriate for someone who may know know whether they have a steam or hot water system, or whether their water make up control is capable of feeding a pool without damage.

[Pete Hughes]

Fair enough.

But the only reason I ever came to this site in the first place, was to find out if anyone had ever built a shallow end for an above ground pool and how they did it. I didn't find anything here, but after I came up with my own solution, decided to post it here in case others like me were looking for ideas.
I would probably have never have come here if all I wanted was "run of the mill" stuff since that is documented in plenty of other places.

I am not suggesting to the OP that this is what he should do or that it is safe in all applications.
It is just what I did. It worked. Even if my idea suggested some crazy “out there” stuff, if I was looking for ideas and everyone else to date had said it can’t be done, I would have been glad to find at least one way to do it. Even if that method was not for me.
I hope a great site that this one continues posting out of the box stuff like this for those that are looking.