leaky fill valve AND shutoff valve

[moray]

Hello toilet experts!

We have a toilet with a fluidmaster 400a fill valve, which I suspect may be leaking due to debris under the valve seal. I have tried to adjust the float height, but that doesn't seem to stop the leaking.

However, the shutoff valve is also leaking, and I'm not sure whether it would be wise to remove the valve cap without first addressing the shutoff valve problem. Will I end up with water spraying everywhere if I try this?

I've tried to turn the packing nut behind the valve handle to temporarily restore the shutoff valve (~1/8th turn clockwise), but that doesn't seem to do anything and I'm afraid to turn it any more since I'm not sure what would happen.

We recently replaced our pump (we're not on a well, but boost the city water pressure since we're up on a hill), so I'm guessing that all of that folderol may have dislodged debris in the pipes?

Please let me know if you have any ideas about what to try next. Maybe I should shut off the water to the house next and go from there, but I was still holding out hope that there might be a simpler fix...

Thanks in advance!!!

[jadnashua]

With the booster pump, what is your actual pressure?

Also, now with the booster pump, you probably have a check valve in the system that may not have been there before. This can cause excessive pressure caused by expansion when using hot water. The cold that gets heated expands, and if you don't have an expansion tank to handle it, the pressure can rise quite high. That high pressure from expansion could cause a toilet (and other things) to leak where they didn't before. Pick up a pressure gauge if you don't have one now in the system, and monitor the pressure after say taking a shower to see what the pressure peaks at.

You'd need to shut off water to the house to replace the shutoff for the toilet...get a 1/4-turn valve rather than a multi-turn one...they last longer (the ball valve doesn't leak as easily as one with a washer in it). You may not get a major spray if the toilet's shutoff doens't stop the flow completely, but depending on the flow, it could spray all over; best to shut the house off while dealing with it and the repair.

[moray]

Thanks for the quick reply!

We do have a check valve, and it never occured to me that pressure could build up past the cut-off pressure of the pump (70 psi) though that makes sense now that you describe it. I'll investigate that further as you suggest.

Is a fluidmaster style fill valve bad news given our setup?

Is there any way to buffer spikes in pressure to protect other fixtures etc?

Thanks again!

[jadnashua]

Now that you have a closed system, you MUST install an expansion tank. Now, sometimes, the booster system has a tank, but that may not be enough, depending on how your pipes are arranged, plus, it doesn't qualify as an expansion tank for water heater purposes and code in a closed system.

With a static pressure of 70#, your peak pressure could easily exceed 140, especially if you use a lot of hot water. The pipes don't expand and the water does...it has to go somewhere and will pick the weakest point to leak from which is often a toilet valve. If that didn't leak at those high pressures, you'd be dumping water from your safety T&P valve on the water heater,or the next weakest link.

Fluidmaster's seals should work fine if you limit your water to 70#. I'd bet it's getting a lot higher from the WH. It's easy to find out, many gauges have a peak hold reading indicator...just install it for a normal 24-hour useage period and see what it says. They're only about $10 at the big box stores or a plumbing supply house.

[moray]

So we have sort of a strange set-up, where the pump stores water in 4 great big pressure tanks (Flotec) before entering the house.

I think this is a reserve for fire-fighting (in case of an electrical fire?) and to have some water when the power goes out. We have a sprinkler system since we're at the top of a hill (hence the pump) and the fire trucks probably can't make it up very well.

I guess that's a long way of asking: do the pressure tanks act as expansion tanks?

I'm pretty sure that the check valve is between the water main and the pump (i.e. upstream of the pressure tanks), but I should go out and doublecheck.

It seems like we'd still exceed 70 lbs if the pump was cycling (or had just cycled), and simultaneous to that we started using a lot of hot water.

I'm a new mom to a 3-month old, so we're having a lot of water issues due to the huge uptick in laundry, dishwashing, showering, baths, you name it.. Our old pump was on its last legs, and within a month of her birth it had died!

Thanks for the tip on the peak hold reading indicator - I had no idea that such a thing existed.. and would be much easier than running out to the pumphouse when we think the pressure would be high

Thanks again!

[moray]

One other question.. would the Fluidmasters tolerate some pressure variability (maybe 60-90 psi), assuming that the pump is set to 60/70 and the pressure tanks partially buffer the heat expansion? (I still need to determine the max pressure in the system.)

Or should we swap these out with another type of fill valve?

Thanks!

[jadnashua]

You don't want your water pressure to exceed 80# normally. If the storage tanks are bladder tanks, functionally, yes they should buffer the pressure from expansion, but it doens't meet the code for an expansion tank.

[hj]

Fluidmasters will handle pressures well in excess of 80 psi, so that is not your problem. The storage tanks are well above what an expansion tank would provide. The only way they are not "code" for an expansion tank is that they are not between the heater and its water shut off valve, but that is also not a consideration for your problem. Whether you get drenched by removing the cap depends on how much the valve is leaking.

[moray]

Thanks hj - that's really helpful!