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 Toilet Keeps Flushing Every 20-30 Minutes; What I've Tried
Author: 120volts (CA)


I have a customer with all the same Mansfield toilets (four) but two of them have the same problem: they leak water every 20-30 minutes and they flush <some> water down and refill, stop, then the cycle continues. About two years ago they had another handyman replace these two toilet valves (Mansfield brand) due to the same problem, but the problem persists. It's hard to say what they replaced as the valves look older than two years to me (corroded screws.)

I have:

1. Cleaned the undersides and mating parts of the flappers. One was particular gummy, but no hard calcium deposits. It seems the flushing may have slowed down but it's hard to judge the customers accuracy. Note: I do see any water moving, so I'm not sure it's the flapper's fault.

2. Opened the valves and cleaned out the two mating diaphragms. On one toilet the black diaphragm stained my hand a bit black when cleaning, telling me it's a bit worn??? Are these standard sizes and replaceable?

3. Before the inspecting and cleaning the diaphragms, I noticed a drip drip sound at the valve. After the cleaning, no dripping per se, but sticking my ear to it I can hear an almost inaudible hissing sound. What does that indicate?

4. The refill tube was properly inserted inside. But I didn't pay attention to see if it was below the "water line." I read after the job that it should be above the water line. Is this true and significant?

What would cause all this and what should be my next steps be in either diagnosing further, or have I hit on a solution? I am trying to avoid replacing with a whole new kit if I can avoid it.

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 Re: Toilet Keeps Flushing Every 20-30 Minutes; What I've Tried
Author: Wheelchair (IL)

Have you considered calling Mansfield Plumbing-customer service dept and requesting their tech service?


Best Wishes

Edited 1 times.

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 Re: Toilet Keeps Flushing Every 20-30 Minutes; What I've Tried
Author: 120volts (CA)

Ah. Thanks! I will give them a jingle. I was going to order their parts anyway and was trying to hone it down a bit. But you're right...they may be able to help me from the start.

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 Re: Toilet Keeps Flushing Every 20-30 Minutes; What I've Tried
Author: hj (AZ)

#4. Yes, and VERY significant.
If the fill valve is leaking, it will either fill the tank to overflowing ane/or discharge water through the refill tube.

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