Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a dual flush toilet that flushes very well some of the time. However, about 50% of the time, when the toilet is flushed and then the hot water faucet is turned on, the hot water pressure dies to almost nothing.

When the toilet finishes filling, one of two things happens:

  • there is sometimes a loud bang in the pipes and then the hot water pressure will return to normal instantly, or
  • when the toilet finishes filling there will be no bang and no return of the hot water pressure until I go to another faucet in the house and wiggle it back and forth between hot and cold very quickly numerous times after which there will be a loud bang and a return of normal hot water pressure.

NOTE: This problem never affects cold water pressure. WHY??? Even our plumber cannot explain it.

share|improve this question
Do you know how many branches come of the supply line into the house before you get to the hot water heater? Ideally, the HWH should be the first branch. – Comintern Jul 16 '14 at 0:09
Does the water coming from the tap stream constantly but with low pressure or does it spurt and slowly gets stronger? Also what is the water supply to your home? City or are you pumping from a lake or well? – Handy Man Jul 16 '14 at 13:48

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.