I have this safety valve installed on cold water inlet of my boiler/water heater. When I turn on hot water tap but keep it around 30%-50% open this valve produces really loud noise, which travels through the pipes and is really annoying. The noise goes away when you fully open the warm water tap.

Given how the valve looks on the inside:

enter image description here

I think the problem is, the spring is faulty, and is vibrating in the low pressure.

Is this a common thing or should I replace the safety valve? I'm afraid replacing it won't solve the problem.

  • What does this valve do? Aug 27, 2017 at 15:21
  • It's purpose is twofold: part A is a safety valve, in case of overpressure on the hot side it opens and the pressure releases to the sink. Part B prevents backflow of hot water back to the mains.
    – jnovacho
    Aug 27, 2017 at 20:07
  • Where are you on this planet? Aug 27, 2017 at 20:28
  • @ThreePhaseEel Central Europe.
    – jnovacho
    Aug 28, 2017 at 6:15

1 Answer 1


Sounds like calcium buildup on the valve gates. You might be able to clean it adequately, if you already have the ability to replace it.

If the springs were bad, I think you'd notice backflow leakage.

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