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condensation on toilet

jumper Member Posts: 1,680
Very cold well water so that toilet bowl literally weeps.
Any ideas? Can electric tracing on supply warm water enough?


  • STEVEusaPA
    STEVEusaPA Member Posts: 5,187
    edited August 30
    No AC in the house? Or AC set too low?
  • Larry Weingarten
    Larry Weingarten Member Posts: 2,246
    Can you "temper" the incoming water with a small tank or length of pipe in conditioned space? That could be a way of warming the water enough to prevent condensation. Another approach would be to mix a little hot water into the cold before it gets to the toilet. Still, heat trace could work! :p

    Yours, Larry
  • mattmia2
    mattmia2 Member Posts: 3,668
    There are mixing valves specifically to solve this problem that mix a little hot water with the cold. There also used to be styrofoam insulation kits for the inside of the tank, not sure if these are still made.
  • psb75
    psb75 Member Posts: 435
    Newer 1.6 and 1.28 gp-flush toilets are filled with less cold water. Kohler and Toto have models with insulated tanks. Probably other brands do also. And mixing valves do work. Plumbing them in is often not convenient. But neither is a warming atmosphere that holds more moisture. See: Ida.
  • Intplm.
    Intplm. Member Posts: 1,331
    @jumper . This is an anti-sweat tempering valve used for stopping the build-up of condensation on a toilet tank. I like to install them behind the toilet so you can't see them.
  • dopey27177
    dopey27177 Member Posts: 717
    Usually toilet bowl sweating occurs when the stopper ball from the Douglas valve leaks or the ball cock is leaking and water flows continuously. In most cases you will not see the or hear the flow.

    Take off the tank cover and check if the water is overflowing from the overflow tube. That that the you need to adjust the the float ball arm, replace the float ball or install a new ball cock.

    If the water is not over flowing you may have to change the flush valve or repair it. Home Depot and Lowes sells those parts.

    Just think about about the sweating on the cold water piping in the wall or ceilings. That wetness can lead to mold or mildew in places you cannot see.

    A nice cheap tool to have in the house is child's stethoscope or buy one at the local automotive supply store.

  • ChrisJ
    ChrisJ Member Posts: 11,844
    May be a less than great idea, but some toilets now have a styrfoam lined tank to insulate it.
    Look up insulated toilets, I think Toto is big on it and they make a good from what I hear. Many say they're the best.

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • psb75
    psb75 Member Posts: 435
    Good suggestion Jake @dopey27177. Important to check tank "innards." Frequent use and flushing is also a culprit that keeps the water extra-cold in bowl, tank, and pipes.
  • mattmia2
    mattmia2 Member Posts: 3,668
    Mine will do it in spring when the incoming water from the river is still around 40 degrees but it is hot and humid outside.
  • jumper
    jumper Member Posts: 1,680
    psb75 said:

    Good suggestion Jake @dopey27177. Important to check tank "innards." Frequent use and flushing is also a culprit that keeps the water extra-cold in bowl, tank, and pipes.

    Yes I was going to post likewise. But don't running toilets show a lot of condensation on supply?
  • psb75
    psb75 Member Posts: 435
    Not usually if it is a plastic or braided metal flex connector. The surface area of the tank's thinner porcelain is the major offender. Newer 'dual flush' tanks can help due to less volume of water moving through the toilet.
    EBEBRATT-Ed Member Posts: 9,678
    Second floor of our condo we don't run the ac up their during the day so tank sweats even though seldom used during the day.

    It's a 40 unit building so the water is always really cold because someone somewhere is always using water. 10 years ago I changed to a Kohler with an insulated tank and that was the fix. Amazing what 1/2" of insulation will do.

    I wanted to put in a tempering valve but it's a second floor bathroom no access to piping without cutting the wall open