Loud Toilet Flushing - New Combi Boiler Installed

[Madrab]

The service valve that is on the supply pipe is half closed, it will create turbulence set like that and turbulence means noise.

It's typical when trying to reduce mains flow to outlets where the mains flow is too high for it when going from gravity to mains. If you open the valve fully, slot in line with the pipe and the noise decreases, then there's your issue. You may then need a new fill valve if it has been running on gravity fed cold water until now.

Agree with others that this should have been considered by the plumbers doing the work. As part of the conversion it is always required to consider the outlets when changing from gravity to mains pressure.

 

[CBW]

The service valve that is on the supply pipe is half closed, it will create turbulence set like that and turbulence means noise.

Good spot

 

[geo-yakult]

The service valve that is on the supply pipe is half closed, it will create turbulence set like that and turbulence means noise.

It's typical when trying to reduce mains flow to outlets where the mains flow is too high for it when going from gravity to mains. If you open the valve fully, slot in line with the pipe and the noise decreases, then there's your issue. You may then need a new fill valve if it has been running on gravity fed cold water until now.

Agree with others that this should have been considered by the plumbers doing the work. As part of the conversion it is always required to consider the outlets when changing from gravity to mains pressure.

good spot too! It’s now fully open but the sound still remains.

I think the pressure of the cold supply needs reducing - anybody have experience with the pressure reducing valves?

 

[JohnD]

Fit a new fill valve suitable for high pressure. Not expensive.

 

[geo-yakult]

Fit a new fill valve suitable for high pressure. Not expensive.

not sure if that will fix the problem though. The water sound appears whenever the cold water is used throughout the house. Taps and toilets downstairs and upstairs in the bathroom.

 

[Harry Bloomfield]

not sure if that will fix the problem though. The water sound appears whenever the cold water is used throughout the house. Taps and toilets downstairs and upstairs in the bathroom.

In that case, it might be worth checking the pressure and flow of your cold water supply generally, then reporting back here.

 

[geo-yakult]

In that case, it might be worth checking the pressure and flow of your cold water supply generally, then reporting back here.

yup that’s what I am going to do