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Neptunebet
Warm to Hot Water in Toilet

We recently noticed that our downstairs bathroom, as well as the upstairs bathroom has warm to Hot water in the toilet.
We have owned this house for 7 years and never had this before.

We first noticed it because when you lift the seat of the toilet this is a lot of moisture on the seat.
Now, when you sit down you feel the heat.

What is causing this?

libcarp
Re: Warm to Hot Water in Toilet

A common practice in some climate areas is to connect the hot water line to the toilet to prevent the tank from sweating.

cjsand
Re: Warm to Hot Water in Toilet

I agree it must be hooked up to the hot water.

MSSP
Re: Warm to Hot Water in Toilet

Did this just start to happen? Or did you just notice this?

dchToh
Re: Warm to Hot Water in Toilet

Here's another possibility: have you installed something recently that might allow the hot and cold water lines to connect to each other? If so, the flush could be pulling hot water from that connection. Something like a mixing valve without adequate backflow protection could do that. Or maybe attaching a Y connector to both hot and cold supplies.

If this has just started happening, I'll bet it's something like that.

dwighthomer47
Re: Warm to Hot Water in Toilet

It sounds logical that the systme is now drawing on the hot more than the cold and their are interconnected.
Along those same lines, I am wondering what would be involved with hooking a tankless hot water heater just for the master bath? Could you just cut into the hot line and run it through? Our bath is away from the hot water heater. Takes many gallons to heat up to use for showering.
Thoughts??

Gray Watson
Re: Warm to Hot Water in Toilet

I agree it might be a symptom of cross-over from any mixing valve. You may have a mixing valve to your toilets (to warm the water a bit by adding a trickle of hot water in with the cold) during a fill cycle to prevent condensation on the tank) and now either the fill valve or the flapper need replacement, this could evidence itself as HOT or very warm water in the toilet bowl when flushed. If so replacing the flapper and/or fill valve would resolve the problem.

I would check the cold water inlet pipe to the water heater, check to see if it feels warm when you notice this. If this occurs only after a first flush after a longer period of no water use (such as being away all day at work) it is not uncommon for hot water to back up into the cold lines during a period of non use when you have a water heating storage tank.

Since you indicate this is a newer discovery after seven years, and if there has been no newer installations or modifications to the plumbing, I'd first investigate and check out the water heater, especially if it hasn't been maintained regularly. I'd be checking the TPRV on the water heater/storage tank, water logged expansion tank, and the setting on the water heater. If a fuel fired direct water heater I'd also be flushing sediment from the tank.

Some closed plumbing systems are designed so that the first sign of water heater troubles show up in the toilet tanks first (esp. if no expansion tank), for example a Watts Governor 80 is designed to vent thermal expansion into a toilet tank. If you have a pressure regulator/reducer on your main/cold inlet it may not be working or may have accidentially dialed up to a higher pressure - thus tripping the Govenor 80 but not enough to lift the TPRV (or the TPRV might be stuck). You can check the water pressure with a guage at any hose bib.

JLMCDANIEL
Re: Warm to Hot Water in Toilet
Neptunebet wrote:

We recently noticed that our downstairs bathroom, as well as the upstairs bathroom has warm to Hot water in the toilet.
We have owned this house for 7 years and never had this before.

We first noticed it because when you lift the seat of the toilet this is a lot of moisture on the seat.
Now, when you sit down you feel the heat.

What is causing this?

Had you recently installed a hot water recirculating pump in the bat rooms to get instant hot water? If it was just installed as a cross over in the baths that my be the cause.
Jack

JLMCDANIEL
Re: Warm to Hot Water in Toilet
dwighthomer47 wrote:

It sounds logical that the systme is now drawing on the hot more than the cold and their are interconnected.
Along those same lines, I am wondering what would be involved with hooking a tankless hot water heater just for the master bath? Could you just cut into the hot line and run it through? Our bath is away from the hot water heater. Takes many gallons to heat up to use for showering.
Thoughts??

A hot water recirculating pump would probably be more cost effective.
Jack

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