advice required for mums house (again) please!

[rocketmanbkk]

Hi Friends

Been to see my mother and another issue!

When she turns on hot water after a while there is a humming noise.

I went upstairs to listen and I think (?) it's coming from the airing cupboard and it maybe something to do with the combi tank?

It sounds like it is humming when the hot is running and the cold is refilling? Never happened before, nothing has been touched etc.

Any advise please as again she now has something else to worry about and is talking about having all her pipes in the house replaced!!!

Thanks

Rocket.

 

[lewisplumber]

Is it the pump?

 

[SimonG]

Incoming water valve on cwsc. Needs a new washer.

 

[rocketmanbkk]

Hi, Thanks for the replies.

The washer on the float valve? I can do that! Just isolate water before, undo and replace. Nice one, I'll give this a try tomorrow.

Lewis - doesn't sound like it's coming from the pump but I'll have another listen, it doesn't happen immediately when hot is turned on.

 

[rocketmanbkk]

I think changing the washer is the cheapest first try? If still humming after I'll get back again.

Thanks so much as always.

 

[lewisplumber]

Make sure you put the washer in the right way round.

 

[lewisplumber]

The washer in the float valve body. It's a big one with no hole in the middle

 

[rocketmanbkk]

Thanks Lewis, I'll let you know how I get on. Cheers

Rocket

 

[gavinwilson]

stop visiting your mother ?

 

[stevetheplumber]

if the cylinder is indirect the pump will kick in after some hot water is drawn of as the stat will be calling due to drop in temp

 

[rocketmanbkk]

Hi, just an update, there is no pump on this. It's gravity fed combi cylinder so I've purchased a new washer and also a new FOV in case it needs changing.

I'll let you know how I get on.

 

[Koogatubac]

How you get on rocketman,

 

[rocketmanbkk]

Hi Friends

Heres the update, changed the washer and plastic thing (any name?)

The noise has gone (hoorah!) BUT can I ask this, when the cylinder start s to fill and is at full capacity the valve takes a while to close fully with a trickle for quite a while, it does shut off eventually and nowhere near overflow or warning pipe.

Is this right? I thought it would have closes rapidly?

 

[JCplumb]

Yeah that's normal.

 

[rocketmanbkk]

Thx JC put my mid at rest!

 

[Bernie2]

The valve is best to close slowly. If it closed fast it may cause water hammer. Basically fast moving water has dynamic energy in it, if you close a valve fast the energy bounces off the valve seating and back down the pipe usually rattling and banging anything loose. There are quite a few kinds of noise caused by water hammer. One common one is that caused by worn washers, usually it is a load thump or vibrations that sound like a hum or whistle. You could go on about it for ages. There is a good site about it just Google "Water Hammer"

 

[fuzzy]

Hi Friends

Heres the update, changed the washer and plastic thing (any name?)

The noise has gone (hoorah!) BUT can I ask this, when the cylinder start s to fill and is at full capacity the valve takes a while to close fully with a trickle for quite a while, it does shut off eventually and nowhere near overflow or warning pipe.

Is this right? I thought it would have closes rapidly?

sounds normal, as long as it shuts

 

[rocketmanbkk]

Thanks again, all.