So.....new plumbing, new floor, new wax ring, new toilet, new fill valve.... there was some grit came out of the old water lines, and the new valve wouldn't shut off when the float got to the top. I flushed the toilet and came back a few minutes later. The floor was flooded. Even though the fill valve didn't shut off, the water should have ran over into the over flow pipe, and it did......yet the floor flooded too. I can't make any sense of it. Can anybody explain why it happened? It only flooded once. Put in another new fill valve and it seems to shut off now. HELP.

Are you sure the gaskets on the tank bolts are not leaking ?
Or the washer on the new fill ( ballcock) is sealing to the tank.


Donnie

I've checked them all numerous times. It only leaked the one time. I'm stumped.

Yep, me too.


Donnie

Grit in the fluid master. If it flushed the valve inside the fluid master clean you should be good now.

Doesn't take much grit to cause it.

Some fluid masters you can remove the top to clear the shutoff valve , some don't.

Good call! It is a Fluidmaster brand!!!

Common brand. Decent. Most assembly like that are just called fluidmaster as slang , like calling a tissue a Kleenex.

They and other brands like them are made sorta cheaply as it is a generic part that fits pretty much any toilet. Most manufacturers make those parts in lower wage countries off shore by the millions.

Grit can sit in pipes for years until disturbed usually when working on the plumbing or a bunch of water flows at a high rate all of a sudden. I've replaced a bunch of the fluidmasters over the years.

Quick tip for the next time or anyone reading this thread , before installing a new fluid master , kinda 'bleed' the line at the shutoff valve near the wall , release a couple gallons at high flow into a bucket before installing the fluidmaster , it clears out the grit before it clogs the new fluidmaster.

Another couple points to consider -

I bet you have good water pressure.

This is why the toilet was able to fill fast enough to overwhelm the overflow pipe and leak onto the floor. The overflow pipe is generally just shy of a inch in diameter as apposed to the drain which is about 2 1/2" . The water will overflow sometimes out of the hole for the flush handle on the side of the tank , then fill the tank to overflowing.

Other things too , don't buy plumbing parts at Walmart or other mass retailers. They sell the cheapest crap. Go to a plumbing supply house where the professionals buy. Better stuff.

Also check your shutoff valve near the wall. If it is getting old , replace it. They always fail in the middle of the night or when you are away on vacation. Get a 1/4 turn one. Much easier to use , lasts a lot longer than an old style needle and seat valve. Check the ones for your sinks too. Yes , they come in chrome finish to match the pipes you have.

Maybe reduce the diameter of your supply line. Should reduce flow rate of water. I am not a plumber, but I have stayed in a Holiday Inn Express.

Is ur plumbing vented to outside. ? Or plug, lot time vent pipe roof, my house never had it when got it 15 yesrs ago. About 10 yesrs ago the plumber put vent in to sewer pipe. Like try fill lawnmower with gas can with vent shut, won't pour right

Sounds like a drain issue. NO fill valve should add water to a toilet faster than it leaves !!!! That over flow tube isn't really there for that .Drain is block and not taking flow of constant flow. Saw 2-3 houses flooded because toilet stuck and filled up septic tank. Backed up and over flowed the toilet . ONe had about 4 ft in basement !!!! Guy flushed his toilet left for 5 hours and came home to that .

My thoughts too.
I'm no plumber but have had a toilet not shut off many times and it never run over. You have to have a drain issue.

Sounds like your trap Is plugged. You have a drain problem.
I had to replace my drain field because of a toilet that didn't shut off. We were at a NTA convention. The toilet never overflowed It just kept running.

That is the only thing that makes sense. I had flushed it a number of times prior to that to see that the fill valve was stopping at TDC. I'll try flushing several times quickly and see if it backs up.
This is a new apartment slapped into the back end of a 100 yr old store building so Lord only knows what's in the drainage system in the basement and below that.

Rooter Rooter.

I am the king of flooded toilets. I maintain 302 toilets daily. Your fluid master valve can fill a toilet faster then the overfill can keep up. Those valves can get plugged with sand or can also get hung up and stick. Been there done that.

you mentioned new floor, how long was the the old toilet removed and the floor flange exposed? Could have someone stuffed a paper towel down the floor flange to block the smell and then maybe it got pushed down a little farther. and not seen You set the toilet and first flush back up but enough force to move the paper towel along its way. just a theory but I have been there

New apartment, new plumbing!!! It is possible.

I've run in to that before.

I agree.

Gary , take a 5gal bucket of water and dump it into the bowl aiming at the drain/outlet. That is the equivalent of 3 flushes of the toilet at once. If it handles it within a 5-10 second interval , you do not have a drain/clog issue.
You did not state you had a slow drain or clogging issue before replacement.
One thing grit/dirt can do is cause the fluidmaster to blow out incoming water under pressure out of the top of the fluidmaster spraying it to the underside of the tank cover (porcelain cover) this will cause water on the floor in a hurry. Changing/cleaning the fluidmaster will fix this immediately. A fluidmaster with grit will only do this once if cleared (flushed clean) or replaced. A clogged drain will do this repeatedly unless for some reason was clogged and cleared one time only.

My bet is grit because you had just replaced everything.

Plus , I don't know if you did this yourself or had it professionally done. Fluidmasters have to be adjusted to proper fill height to the waterline. Also , the overflow tube needs to be cut to about 1" above waterline (proper fill height) you may seen in some toilet it has been cut (crudely sometimes with a hacksaw) to be at the right height to meet code.