Noise Coming from Loft Water storage tank?

[wild nomad]

Hi there,

Just had the following email from one of my customers:

''we have a very loud noise coming from the loft like an underground train. It is intermittent but quite alarming at times accompanied by a banging noise.''

This is about a month or so after I installed a new CWSC and F&E tank. All building regs and British standards were adhered to. It sounds a lot like water hammer to me.

The old float valve they had was letting by some what so the new one maybe causing water hammer because it's working too well. I could look at putting in more clips and an arrester but since I can't get round to look at it till the weekend thought I'd have a brain storm with you guys and see if anyone can think of what it might be if it's not water hammer.

Thanks in advance

 

[SimonG]

Might need a few more clips. I had a new one that resonated, fitted a bit of 3 x 2 and a couple more clips and it was sorted.

 

[kris]

I know its new but it wouldnt surprise me that the diaphragms went already, wouldnt think so but you never now , or it may be the stopcock hammering , is the stopcock new or is it the original one ,

 

[wild nomad]

I know its new but it wouldnt surprise me that the diaphragms went already, wouldnt think so but you never now , or it may be the stopcock hammering , is the stopcock new or is it the original one ,

Yes, original stopcock located in the kitchen.

 

[kris]

No i mean stopcock to isolate the tank in loft ? soz

 

[wild nomad]

No i mean stopcock to isolate the tank in loft ? soz

Yes, it's new. It's a service valve so connects straight on to the float valve thread.

 

[Dazh09]

Sounds like the ball valve is oscillating, close the incoming stop valve slightly to reduce the incoming flow, otherwise use a larger ballfloat or damping plate fitted to the ball valve lever, alternatively baffle vanes fitted inside the cistern to prevent waves from forming