Sticking Toilet Mixing Valves

Toilet Flapper Problem

• The mixing valve will often appear to fail if there's a problem with your toilet flapper. If the flapper doesn't create a proper seal between the toilet and the plumbing system, water leaks out of the the toilet tank into the bowl. The toilet flapper generally pulls this water from the warm water supply in the mixing valve instead of the cold water supply in the tank. Thus, the water temperature in your bowl will gradually rise.

Fill Valve Sticks

• If your fill valve sticks or doesn't completely close, too much water goes into your bowl and the mixing valve can't work properly. As with toilet flapper problems, fill valve problems often lead to the water in your toilet being too hot. A steady supply of water leaks due to the fill valve problem, and this water tends to be hot water rather than cold water.

Symptoms

• If your mixing valve is sticking or there's another problem, you'll see water condensing on the side of your toilet. You may also find that water in other parts of your home is too hot; you may need to adjust your shower water temperature or be unable to get cold water when washing your dishes. A stuck mixing valve also causes the toilet to flush very loudly.

Importance

• Although the water temperature in your toilet may not seem like a significant issue, you should take care of mixing valve problems right away. If your water temperature gets too hot due to a mixing valve problem, you or your children may burn themselves while using water. In addition, hot water breeds bacteria and disease. This is especially a problem around the toilet, since you dispose of unsanitary waste in this area.