Toilets are filling with hot water

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Klynne

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I was trying to install a very simple hand held sprayer to my toilets water supply with a t-valve. I followed installation directions perfectly, then when I turned the water valve supply back on the water was hot. I went to my other toilet and turned off the water supply, disconnected and reconnected the toilet hose, but did not install a sprayer in this one, and now that toilet is filling with hot water too. Anyone have any thoughts or ideas? The toilets are both less then 6 months old...
 

breplum

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Age of toilets have nothing to do with it. Cold water supply is cold water supply.
Possibilities:
You could have hot water piped to the WC.
You could have a problem with crossover coming from a plumbing fixture.
I have seen many, many circumstances, where a KWC or Kohler pressure balancing shower valve internally allowed hot to cross over.
 

SHEPLMBR

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Maybe it has been that way and hooking the little dohicky up, you just now noticed it.
 

Jeff Handy

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As mentioned, very possible that a faucet cartridge is bad and allowing crossover through itself.
It can be a shower, tub, or sink faucet cartridge.
I have seen Moen cartridges do this also.
 

Aloha Mark

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As mentioned, very possible that a faucet cartridge is bad and allowing crossover through itself.
It can be a shower, tub, or sink faucet cartridge.
I have seen Moen cartridges do this also.
I'd go with this theory, though it seems unusual that this started happening with the act of installing a sprayer to the toilet line. Could we see a photo of that installation?

At a home in Pittsburgh, I noticed that the hot and cold supply lines in a bathroom were reversed. Hot water always flowed through the toilet bowl when it was flushed. The owner used a handyman carpenter, not a licensed plumber.

Once upon a time, I hooked a washing machine to the supply bibs, and "accidentally" reversed the hot and cold lines. A woman was giving me advice to hook the hot hose to the right and the cold hose to the left. One load of clothes were ruined. Of course, my revisionist thinking says that I will always get into trouble listening to a woman.
 

Jeff Handy

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The old rule “Hot is always on the left” has exceptions.

Most often if two bathrooms are back to back, then sometimes one has the shower or tub valve special ordered to be a reverse feed valve.

And sometimes you will find even the sink supplies are reversed, on one of the back to back sinks, so you have to hook up to them with crossed supply lines.

And a laundry room that backs up to a kitchen or bathroom can have reversed supply valves.

And of course, if uncle Joe or cousin Moe did the rough in on something, getting paid in beer and pizza, things can get backwards pretty easy.
 

fixitron

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Sometimes toilets are installed with an anti-sweat mixing valve that mixes hot water with cold to prevent condensation on the tank. This valve would be in the wall behind the toilet.
 
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