Water level rising with no rain

[jtb777]

Hi all,

Today, I noticed my pool’s water level rose about a 1/4 inch last night. It’s been overcast and foggy, but no rain last night as far I can tell from weather reports.

I do have an auto-fill feature, and I’m not sure if it’s malfunctioning. (Pics attached.)

I’m not sure how auto-fills are supposed to work and what it’s supposed to look like when operating correctly. I don’t hear any hissing sounds from the auto-fill, or see any obvious leaks around or near the pool.

I'm hoping to figure out what's causing the problem so the water doesn't keep rising.

Thanks for any replies!

 

[HermanTX]

The auto fill works like your toilet valve. When you flush, water begins to fill the tank and then is stopped when the float rises to shut off the valve which shuts off the water. So what may have happened is your float is set too high, allowing water to continue to fill. see the gray knob - turn that counterclockwise to lower the water level at which the valve will close. Now it will not drain your existing level, but it should stop the filling process.
If that float/valve is not functioning, then that could allow the water to continue to be added to the pool. You will need to change out that float/valve assembly.

 

[Dirk]

In a write-up I'll eventually get to, I'll describe how I added a water meter to my auto-fill line. I had the same exact symptoms as you, for who-knows-how long, and the water meter has led me to the fix (though I've yet to do it to confirm). It has to be my auto-fill "toilet" valve. I don't know where else I thought the extra water could have been coming from, but the "non-hissing" had me stumped, too. One of two things is happening: either the valve is leaking in such a way that it makes no noise at all when it does, or the cover of the well, when replaced, presses down just enough on the lever to operate the valve. So I don't hear it when I check it, but turn it back on when I cover it back up!

Either way, the water meter's leak detector (flow indicator) doesn't lie. So I purchased three new valves from Lowes for $21. For seven bucks a pop I'm just going to replace that valve every year or two. The water meter will keep me apprised of the valve's status, and checking it will become part of my weekly equipment inspection.

So, sorry, short version: for less than 10 bucks, change out the valve and see if that solves the problem. Cheap troubleshooting (and you probably could do for a new one even if that's not the problem). I feed my pool filtered, near-zero calcium water from my house's water softener, but I'm sure some minerals still sneak through. Enough to eventually collect on the valve and compromise it. It's why my first one went, and must be responsible, at least in part, for this second failure. Plus, they're just uber-cheap mechanisms. Regular replacement will hopefully solve the problem going forward.

While even I thought it was a bit silly to install a dedicated water meter just for my pool, it just paid for itself! I had given up trying to figure out why my pool's level was always higher than it should be, and I probably would have continued pouring water and money down the drain (literally). So the water meter is a welcome addition.

 

[JoyfulNoise]

That looks like a standard toilet bowl float valve. Did you have that replaced recently?

Standard toilet bowl float valves should not be used with pools. There’s versions of the Korky fill valves that are specific for pool use. My guess is the internal rubber bladder on the float valve is damaged. Not worth replacing the bladder, you’ll never get the valve sealed up right. Just buy a new float valve, one intended for pool use.

Also, consider adding a debris screen to the bottom of the valve where it screws into the well (similar to the screens you put on washing machine lines). Any little debris in the supply water can cause the valve to get jammed open.

 

[Dirk]

Ah, Matt beat me to it, but I'll finish typing anyway...

FYI: the correct replacement part for a pool auto-filler is slightly different than the one used in a toilet tank. An auto-filler valve doesn't have that black tube. It might have the barb fitting on which a tube could be pushed, but it's actually plugged up. That said, I'm going to try a toilet valve anyway, to see if I can get it to work correctly, and just keep a close eye on it until I can confirm it works or it doesn't. I plan on plugging up the barb. I've examined/compared the correct part to the "toilet" version and cannot find any other difference. Maybe I'll burn one and take it apart and compare guts just to confirm.

More to the point, those valves emit water in two places, through the tube, and out the bottom. Just because the tube is not showing a leak, doesn't mean it's not leaking out the bottom.

You'll find the correct part in the $30-40+ range online. Like I said, I got three for $21. I figure that kind of change (considering I'll be replacing mine regularly) is worth a little experimenting.

 

[JoyfulNoise]

The black tubing is meant to fill the toilet bowl while water emitted from the bottom valve fills the tank. Obviously this is not a toilet bowl so the black fill tube is unnecessary.

Pool leveler valves are more expensive because they use slightly different rubber materials for the internal bladder and o-rings to ensure that the valve is compatible for an outdoor environment and with possible exposure to highly chlorinated water. Standard materials will not last as long. This is why you always see two kinds of flapper valves in a hardware store - one for well water (no chlorine) and one for city water (chlorinated). If you use the wrong flapper valve in a toilet tank, the chlorine will destroy the rubber material very quickly.

 

[Dirk]

Good to know.

 

[jtb777]

The auto fill works like your toilet valve. When you flush, water begins to fill the tank and then is stopped when the float rises to shut off the valve which shuts off the water. So what may have happened is your float is set too high, allowing water to continue to fill. see the gray knob - turn that counterclockwise to lower the water level at which the valve will close. Now it will not drain your existing level, but it should stop the filling process.
If that float/valve is not functioning, then that could allow the water to continue to be added to the pool. You will need to change out that float/valve assembly.

Thank you!

 

[jtb777]

In a write-up I'll eventually get to, I'll describe how I added a water meter to my auto-fill line. I had the same exact symptoms as you, for who-knows-how long, and the water meter has led me to the fix (though I've yet to do it to confirm). It has to be my auto-fill "toilet" valve. I don't know where else I thought the extra water could have been coming from, but the "non-hissing" had me stumped, too. One of two things is happening: either the valve is leaking in such a way that it makes no noise at all when it does, or the cover of the well, when replaced, presses down just enough on the lever to operate the valve. So I don't hear it when I check it, but turn it back on when I cover it back up!

Either way, the water meter's leak detector (flow indicator) doesn't lie. So I purchased three new valves from Lowes for $21. For seven bucks a pop I'm just going to replace that valve every year or two. The water meter will keep me apprised of the valve's status, and checking it will become part of my weekly equipment inspection.

So, sorry, short version: for less that 10 bucks, change out the valve and see if that solves the problem. Cheap troubleshooting (and you probably could do for a new one even if that's not the problem). I feed my pool filtered, near-zero calcium water from my house's water softener, but I'm sure some minerals still sneak through. Enough to eventually collect on the valve and compromise it. It's why my first one went, and must be responsible, at least in part, for this second failure. Plus, they're just uber-cheap mechanisms. Regular replacement will hopefully solve the problem going forward.

While even I thought it was a bit silly to install a dedicated water meter just for my pool, it just paid for itself! I had given up trying to figure out why my pool's level was always higher than it should be, and I probably would have continued pouring water and money down the drain (literally). So the water meter is a welcome addition.

Very helpful, thank you so much!

 

[jtb777]

That looks like a standard toilet bowl float valve. Did you have that replaced recently?

Standard toilet bowl float valves should not be used with pools. There’s versions of the Korky fill valves that are specific for pool use. My guess is the internal rubber bladder on the float valve is damaged. Not worth replacing the bladder, you’ll never get the valve sealed up right. Just buy a new float valve, one intended for pool use.

Also, consider adding a debris screen to the bottom of the valve where it screws into the well (similar to the screens you put on washing machine lines). Any little debris in the supply water can cause the valve to get jammed open.

Hi, I bought the house a couple months ago, so I'm not sure when it was last replaced. Thank you for mentioning there's a float valve for pool use, and the debris screen. So helpful to a newbie like me!

 

[Dirk]

Hi, I bought the house a couple months ago, so I'm not sure when it was last replaced.

Most auto-fill owners don't know the difference (and I'm still not 100% convinced there is one, other than the tube). So yours was probably replaced by the last owner, trying to save some bucks (just like me!). I'm going to call the company or take one apart to get to the bottom of this, because it's come up before on the forum.

I bought a cheap one to replace an "official one," and examined both exteriors closely. Even the part numbers are the same. I even still had my first one, and it too was identical save the tube port. But Matt's explanation is plausible enough to give me pause. So I'll go digging when I have time. In the meantime, mine is currently leaking so I'm going to use one of my toilet valves until I can get to the "investigation." Seven bucks will solve my immediate need. I can always spend more later and use the other two in my toilets!

 

[Dirk]

OK, so here's what I have so far. "Official" auto fill valve on left, $7 Lowes toilet valve on right. Both are from FluidMaster. I obtained my 1st replacement auto-fill valve directly from the auto-fill manufacturer (POOLMISER), for about $25, which matched exactly the one I replaced (they use FluidMaster). The first one probably lasted about 4-5 years, the second one about the same. The first one was subjected to my city's very hard water, the second one only had filtered, softened water run through it. Both have been subjected to up to 3500ppm saltwater, chlorinated. The current one is still in my pool, the one pictured is the first one I had.

I don't actually have any way to determine if Poolmiser is using the same type of valve you see for $35-40 (like Pentair's). Maybe they just use a cheap toilet valve. So that aspect of the comparison may fall short. Someone that buys the Pentair model will have to fill in the blanks here. But... if Amazon's photography is to be believed, the Pentair part is indeed FluidMaster, and looks to be absolutely identical in every way to the part I am replacing (except for the part that screws into the well).

https://www.amazon.com/Pentair-T29-Fluidmaster-Replacement-Automatic/dp/B004VU8TBC/

The only noticeable difference between my old valve and the Lowes valve is the way the port for the toilet bowl filler tube is blocked in the Poolmiser version, where it is open in the Lowe's version. Other than that, the parts are all near-identical. Some of the markings are different, and the piece that screws into the well is slightly different, but functionally identical, as they each extends just as far. I disassembled both models. Identical. If the bladders are of different material, that is very likely the only possible difference. They have a different sheen to them, but one is been in the pool for five years! It would have been conclusive if they were marked identically, but the Poolmiser version has a part number, the Lowes version does not.

One thing of note, the black cap of the Lowes version specifically warns about adding chlorine to the toilet tank. "Ah ha!" I thought. So I checked the Poolmiser version and... it carries the same warning! But, to me, that only means FluidMaster is using the same part for both.

Since I am still inclined to change these out every year or two, I'm gunna unscientifically "pre-conclude" that the Lowe's model will be fine. Either way, I'll report back in Spring of 2024, unless it fails before then.

I don't think the thumbscrew adjuster of the Lowes model is going to fit in my well, as that part gets very near the underside of the well's cover. I'll either use the old one (they're interchangeable), or I'll just hacksaw off the thumbscrew and adjust it with some pliers. Note the bowl filler port is blocked in the Poolmiser version. This is the part that had different markings. The floats are identical, with the same part number. The part number on the float (400) is the entire valve's part number (not just the float's part number). But to me that doesn't mean much. You can definitely see how the chlorine affects the grey plastic.


The Lowes model seems to be date-stamped. It looks like "30-08-22."


One could definitely argue these are not made of the same stuff, but the one on the left has been in my pool for years.


The lever mechanism looks to be identical.


Here's the only other real difference between the two, but they'll both work exactly the same in my well.



I think there might be another gasket involved. Perhaps one inside the tubes somewhere. I couldn't get at that one, if it's there. But my future tests of either version will be performed by the flow indicator of a dedicated water meter, which will reveal the tiniest leak instantly, even if it can't determine what exactly is leaking or why. It's academic. If a $7 valve doesn't leak for two years, I'm good-to-go. If it does, then I'll pay the $40. Either way, I'll now know if and when they fail, because checking that water meter flow indicator is now part of my weekly routine.

 

[JoyfulNoise]

I think the biggest issue with those valves is the rubber bladder. Any small amount of debris or buildup will cause them to leak. I have a horizontal ball float valve that simply uses a pinhole and plastic “nub” as the stop. There’s literally nothing that can clog it up and it has worked flawlessly for 10 years. I have no idea why the pool industry went to using toilet bowl valves but they are worse than the old school float valves. Basically they created a solution in search of a problem and made autofills less reliable, not more.

 

[Dirk]

I think the biggest issue with those valves is the rubber bladder. Any small amount of debris or buildup will cause them to leak. I have a horizontal ball float valve that simply uses a pinhole and plastic “nub” as the stop. There’s literally nothing that can clog it up and it has worked flawlessly for 10 years. I have no idea why the pool industry went to using toilet bowl valves but they are worse than the old school float valves. Basically they created a solution in search of a problem and made autofills less reliable, not more.

I can attest. The first one went because I was working on the line to it, and I probably introduced some crud, or knocked loose some deposits. But the second one has only been fed a steady diet of filtered, softened water. I'll know more when I take it apart after replacing it, but they're just not all that reliable. Why did they go that way? Same reason as everything else: they're dirt cheap so increase profits.

 

[JoyfulNoise]

Why did they go that way? Same reason as everything else: they're dirt cheap so increase profits.

I don’t know. My bulb style float valve is waaaay cheaper than any toilet bowl style float. It’s literally just a plastic armature and a plastic bulb that floats horizontally in the fill pot. They are very commonly used in swamp coolers too. In fact, the ones used in swamp coolers are probably more expensive because the valve body tends to be made of brass. My pool leveler valve is entirely plastic. Cheap, simple, but incredibly reliable.

Maybe @1poolman1 or @AQUA~HOLICS has some insight given their many years of experience with pools.

 

[Toxophilite]

I don’t know. My bulb style float valve is waaaay cheaper than any toilet bowl style float. It’s literally just a plastic armature and a plastic bulb that floats horizontally in the fill pot. They are very commonly used in swamp coolers too. In fact, the ones used in swamp coolers are probably more expensive because the valve body tends to be made of brass. My pool leveler valve is entirely plastic. Cheap, simple, but incredibly reliable.

Maybe @1poolman1 or @AQUA~HOLICS has some insight given their many years of experience with pools.

My current plan is to get a 3/4" straight pipe to 1/2" tapered bushing and build a standpipe with a good, brass, horizontal float assembly. It'll take a little planning and doing to source sized enough components to fit the can, but currently, I spend more time "tweaking" with the stupid toilet bowl assemblies than anything else on my pool.

 

[Dirk]

My current plan is to get a 3/4" straight pipe to 1/2" tapered bushing and build a standpipe with a good, brass, horizontal float assembly. It'll take a little planning and doing to source sized enough components to fit the can, but currently, I spend more time "tweaking" with the stupid toilet bowl assemblies than anything else on my pool.

Deets! Please post your efforts as you progress (so I can copy them)!!

 

[AQUA~HOLICS]

This is the only style auto fill I have any experience with, it’s the only type I have the plumber install.

 

[Toxophilite]

Deets! Please post your efforts as you progress (so I can copy them)!!

Will do! I think after seeing aqua-holics posted pics, I will need to jog the line over to side, and the constraint will then just be elbow+float assembly fit across can.

 

[JoyfulNoise]

This is the only style auto fill I have any experience with, it’s the only type I have the plumber install.View attachment 462552View attachment 462553

That’s exactly the one I have. They are incredibly reliable. I have no idea why pool builders choose to install the toilet bowl ones. My one thought was that maybe you can make the fill pot smaller with the toilet bowl version and so there’s less impact on the pool design by not having a big fill pot sitting on your deck somewhere but I really can’t believe it would save that much space.