Rattling Central Heating Valve...I think?

[ajborissow]

Hi All,

Can anyone tell me what the below is please. Whenever the boiler switches on and the central heating fires up there is a really noisy vibrating / rattly noise that comes from it. It's so noisy now it wakes everyone in the morning when it comes on. If it's just the hot water then no noise.

Any help would be greatly appreciated.

Many thanks,

Andrew

 

[GasmanxxxR1]

That is possibly an none return valve, where abouts on the system is it?

 

[ajborissow]

The boiler is just to the left of the pipe not even a foot away

 

[GasmanxxxR1]

I would say it is a none return valve that has failed or has something stuck in it. Have you a fully pumped system or is the hot water on gravity feed from the boiler?

 

[ajborissow]

I dont know to be honest, the boiler is down stairs in the kitchen and we have a hot water tank upstairs. We have 2 tanks (1 feeder) in the loft to feed boiler and taps etc

 

[GasmanxxxR1]

The valve will need replacing or if its a fully pumped system removing, perhaps get a heating engineer in to fix

 

[ajborissow]

Excellent, thanks for your help

 

[rogerp]

Hi,

The valve appears to be an anti gravity valve which would suggest that your system is gravity circulation on the hot water.If you have 4 pipes coming from the boiler it is usually a good indicator,two gravity circs to cylinder and two to pumped heating. The gravity valves eventually stick and means that you get a judder as the hot water rising to your cylinder forces its way through the valve. You are still able to get these from plumbers merchants but it is likely to be an order in item and not something they will have on the shelf.
Get a heating engineer in to change it for you as the drain down can be problematic (defective drain cocks) and subsequent refilling can be prone to airlocking.

Hope this helps
Rogerp