Can I use this to add water to my pool?

Bwdonohues58

Gold Supporter
In The Industry
Apr 22, 2019
129
Homer, AK
Pool Size
10300
Chlorine
Liquid Chlorine
When I set up the plumbing, I had them put in this tee with a hose bib so I could lower the water level in the Swim Clear filter when it was time to change out the cartridges. I now want to use this as a way to add make-up water to the pool. It usually requires an inch or two once a week. It's between the pump and the filter. I can attach my hose to it from a nearby sink. Does anyone see any problems with this? What I do now is run the hose out to the pool and fill it that way. I don't like doing this when there are people using the pool. To me it might be OK, but I don't want to do it if it might cause a problem downstream. The heater is next in line downstream from the filter.
 
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You lack a back flow preventer or air gap and can end up feeding pool water into the house and municipal water system.

The pool water pressure is likely higher then the hose pressure and water will not flow into the pool while the pump is running.
 
You can't use that hose bib as is to do what you want to do (not safely, anyway). But... while it is not standard practice, you could use your pool's existing plumbing to fill your pool. You'd need:

- a water source (better than a hose run to an indoor faucet),
- to fill only when the pump is off,
- a proper backflow preventer, and
- a couple of check valves.

The check valves would go somewhere near the end of your pad's plumbing (just before the plumbing heads off to the pool). One would prevent fill water from running backwards through your pad's components and plumbing (especially the filter). And the other would prevent pool water from pushing its way back through your fill source (while the pump is running). Even with that, you'd still need a proper backflow preventer somewhere between the water source and the pool plumbing.

Alternately, there are systems that connect directly to your pool's plumbing that maintain the pool's water level automatically. Pentair sells one (though I'm not sure it works without a Pentair automation controller). There are others. These devices monitor pressure in the plumbing (and a few other things) and inject water as needed, but only when the pool pump is off. If you've got some bills to throw around, that would be more convenient than adding water everyday manually with the plumbing mod described above.
 
If you want to pursue this, there might be a better way than what I originally suggested. You could do it with one less check valve if you injected water into the plumbing leading to your pad, not away from. If the fill water enters before anything else, it doesn't matter which way it travels. If it tends to go towards the pad, that's the normal flow direction, so that's fine. If it tends to flow back to the pool, that won't affect anything on the pad (like the filter), so that is also fine. You wouldn't want to add water between the pump and the filter (where your bib is now) because that could push the gunk that collects in the pump's basket back towards the pool...

You can learn more about backflow preventers here:

 
Thanks Dirk. I also have another tee in place down stream from the heater and also down stream from the check valve that protects the heater. I could easily add a similar hose fitting in this one. It’s just 3-4 feet above the mop sink. Think this might work? Here’s a photo. 7EE7D68C-7D96-4159-81AF-95D4BFF39FD5.jpeg
 
Where does that 2" pipe go? (Off to the right?) Does that go directly to the pool?

And is that 3/4" PVC pipe down below a water source? Seems like you've got the makings. You'd add a BFP valve to the 3/4" line and run that into a reducer fitting (to go from 3/4" to 2"), then a check valve, then into that tee.

If there are other components after that tee, then that might be an issue.
 
Here’s a better photo. The ¾ inch line is just a drain that has nothing to do with the pool plumbing. The Clear Comfort AOP and the UV Spectralight just have water passing through them. The last thing in the stream is a Stenner pump and tank combo that puts liquid chlorine into the poolThe 2 inch pipe goes into the crawl below and the water returns to the pool. I really don’t think that water from a hose would be any different than pool water from the pump. D58EF6D1-68E0-42CC-BD46-788B29A0DD81.jpeg
 
It's probably fine to inject water anywhere after that check valve following the heater. Technically, if you have a check valve anywhere in the loop, even before the filter, water injected anywhere after that is not going to go backwards. That said, I'd add a tee after the Stenner injector and do it there. Because of that second check valve, adding water after that one would 100% eliminate any sort of issues with all the various gizmos you've got going on.

Is that a sheetrock wall? You could open that up and stub out a cold water pipe from whatever is feeding that faucet, to feed the pool. Then patch up the wall. You'd plumb in a BFP into that new line, then feed that into a third check valve and then from there into the new tee. That's the right way to do it. The BFP will have a valve on it, to control the fill.

Of course you could use a hose and a simple valve, like you originally wanted to, but I can't officially endorse that, as it circumvents the safeties Allen and I pointed out to you. I prefer to do things the right way. Sometimes the logic for why building codes exist are not always obvious, but they do exist for a reason...
 

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Of course you could use a hose and a simple valve, like you originally wanted to, but I can't officially endorse that, as it circumvents the safeties Allen and I pointed out to you. I prefer to do things the right way. Sometimes the logic for why building codes exist are not always obvious, but they do exist for a reason...

Considering @Bwdonohues58 has a commercial therapy pool I think he should do things the right way.

But then he is in Alaska. :scratch:
 
Right, I didn't connect the dots to "commercial." The time and money you might save by short-sheeting this project would probably come back to haunt you at some point... I'm now picturing some sort of inspector sniffing around your pool gear...
 
Thanks for all the good advice. BTW, I called Alaska DEC last April and they said that a Physical Therapy pool is private and not subject to all their regs. I don't need a certificate, etc. That said, I have all the regs printed out and try to comply with them all.
 
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The pool water pressure is likely higher then the hose pressure and water will not flow into the pool while the pump is running.
Typical city water pressure should be above 40 psi.

Most pool pumps can't get to 40 psi.

So, it would be unusual for the system pressure to be higher than the city water pressure.
 
Most of the sweeps are DWV, which means that they are not pressure rated.

That’s a disaster waiting to happen.

If you paid for this to be professionally installed, have the plumbers come back and do it right.

The two highest sweeps are pressure rated.

The pressure rated sweep has a deeper socket depth than the non-pressure rated sweeps.

The difference is easy to see.

d58ef6d1-68e0-42cc-bd46-788b29a0dd81-jpeg.170694


If you want to connect a fill line to the plumbing, it has to be done with an approved backflow preventer and anti-siphon.

 
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Most of the sweeps are DWV, which means that they are not pressure rated.

That’s a disaster waiting to happen.

If you paid for this to be professionally installed, have the plumbers come back and do it right.

The two highest sweeps are pressure rated.

The pressure rated sweep has a deeper socket depth than the non-pressure rated sweeps.

The difference is easy to see.

d58ef6d1-68e0-42cc-bd46-788b29a0dd81-jpeg.170694


If you want to connect a fill line to the plumbing, it has to be done with an approved backflow preventer and anti-siphon.

Nice setup!
 
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