Clicking radiator!

[davecon1]

Can anoyone shed some light on a problem that's been driving me mad recently. For the last few weeks the radiator in my bedroom has started clicking in the morning when it comes on (and the evening but it's not a problem at that time of day). It clicks about once every 3 seconds for 4-5 minutes and then dies down and it's enough to wake you up.

I've read some similar posts and as a result have bled the radiator, banged it (that works quite well for a minute or two), checked the TRV (ok) and also checked that there is cushioning on the metal bracket (there is).

I'd be grateful for any advice- I cannot sleep in any more!

 

[gas4you]

Check that one of the plastic fittings between the rad and its brackets has not disintegrated.

Other than that could be pipes under the floor rubbing on joists etc.

 

[davecon1]

Thanks for that information. I did check the plastic fittings and they seemed to be in place although I didn't chance taking the radiator off as it's huge.

Oddly enough the clicking has stopped but I have noticed that there is a slight whistle coming from the TRV. When I turn it slightly it stops.

On the subject of valves I've also noticed that my bathroom towell rail stays on full blast no matter what the thermostat setting (unless it's off). I'm guessing the TRV must be broken unless it's due to the fact it's plumbed into the hot water.

 

[cjb1971]

Your towel rail is probably fitted without a trv,most of these are,this will then also act as a bypss should all the other rads close off on their trv`s.

 

[davecon1]

Unfortunately it does have one. I guess maybe the sensor isn't working anymore?

 

[davecon1]

Aha.

I've worked something out. The clicking noise and the hissing started again this morning a day after i regenerated the air gap on my megaflo. This would suggest to me that:

A hissing sound is because the flow-rate is too high through the valve, caused by the pressure being too high.

A tick-tick-tick sound indicates there is tension in the system in the pipes.

Not sure how to resolve it though. My megaflo is not balanced which is why I need to regenerate the air gap every 3 months.

Any ideas?