11 February, 2017

In the Pool Again

It's still cool, even brisk, getting into the pool. But after you freeze the nerve endings, it seems to be quite comfortable.

The hardest part of getting in the pool at this time of year is, as you might expect, getting in. Yesterday, the temperature in the pool made it up to a bit more than 80° (f).

Denis and I Breaking It In
You might say, what' to complain about? And, you'd be right. We ain't complaining, we're enjoying. But keep in mind, we're used to daytime temps being in the low nineties, even in winter, so to get into the pool, is a breath-taking experience.

After you've been in for a minute or so, it becomes a very comfortable experience.

Construction work for the pool is all done. That doesn't mean that all 'work' is done. For example, I still have to install the solar heating system. I already have the pump and the solar panel for that. Just yesterday I ordered the heating collector - a plastic panel, 2' x 20', that is filled with little tubes, that heat the water as it passes through them.

It's been tempting to over-engineer the heater bit. Everyone wants to sell you a heating system that will make hot water. I don't want to make hot water. I just want it to be warm. At the most, I want the water to go up eight degrees. Eighty-four degrees is about optimum for us. that's quite comfortable.

Thanks to Denis, who found a website that talked about determining BTU's (British Thermal Units), which in turn, led to me finding a website that gave a good method of determining what size heating system we need. I'm not saying this is absolutely the most correct way to do things, but it is the most logical-seeming to me, and that's what I'm going by. And, it's relatively cheap and easy to do to.

Here's the nitty gritty on what we found.


Serious Mathematics Ahead. Proceed at your own risk.

First, you have to know (or calculate) how many gallons of water your pool contains.

We did that. It's 9,000 gallons.

Then you have to determine how long it takes to increase your pool water temperature by 1° (f).

To do that, multiply the total gallons of water in the pool by 8.3 (One gallon of water weighs 8.3 pounds). This will give you the total weight of the water in your pool.
(9,000 gals. x 8.3 lbs = 74,700 lbs)

Then, divide the total weight of the pool water by your heater's or collector's BTU rating. Finding the BTU for some of these heating systems can be a challenge. I stumbled on one that was similar in size to the collector I was thinking about buying. It was rated at 40,000 BTU. That seemed reasonable, so I used that as my BTU rating figure (hey, it's not an exact science here. We're talking ballpark guestimation all the way around). Call it an experiment.
(74,700 lbs. / 40,000 BTU = 1.87 hours)

Now, determine the total time required to increase the pool water temperature the desired amount.

I used 76° (f) as my current water temp (which seems that ours is most of the time during the winter here, as long as we keep the pool covered at night and when we're not using it).

I want to raise that temp to 84° (f) for a total of eight degrees.
Multiply eight degrees by the time it takes to raise the temperature 1 degree (f)
(8 degrees x 1.87 hours = 14.96 hours)

So, the best minds in the business (Denis and me) think this is acceptable. Roughly 15 hours of heating to get the pool up to the 84° (f) threshold. Since we really didn't get into the pool until it was 79° (f), we should be able to shorten the time. But we really don't care. It can take two or three days to heat up. That's fine. Again, we're not creating hot water for household use, just warming the pool.

Once I get the solar panel and the pump installed, it's simply a matter of waiting till the collector arrives, and hooking it up. Then we can begin keeping track of pool temps and how fast/slow things heat up. Till then, it's all guesswork, which is our forte anyway. I'll let you know how things progress.

We'll probably get it hooked up in time to shut it down for the summer season anyway. But, if that's the case, we'll be ready for the cooling days of next fall and winter.

Serious Math Warning Terminated. Relax and have a beer

 I don't remember if these shots were taken before or after the math workout. In either case, we have safety Belikins in hand.

Very Comfortable Dry Run
 The pool is functioning superbly. The waterfall (the stone area in the background) also works great. We don't have it turned on in these photos for some unknown reason.

Even Maggie Gets In the Act
Thanks to Vivien for taking these photos for us. I wanted to show folks that, yes, the pool is back functioning. She did a nice job of it too.

Their little dog, Maggie even helped.


Vivien said...

Being in 81F or 27.2C water is a very comfortable for us northerners. The only time it felt chilly was for 3 seconds during the initial entry, after that it was lovely.

SJam said...

Looks super! I like the waterfall and structure surrounding the pool.

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Winjama said...

Hi Vivien,
This is about the fifth attempt to post a reply. Thanks for your comment. The pool was warmer yesterday.
Thanks again.

Winjama said...

Hi SJam,
Thank you for your comment. The waterfall turned out far better than we could have hoped for. We're very happy with the whole thing.