Clonk, clonk, clonk ...

[mlse]

Hi all,

I have a mysterious noise in my house!

In February of 2007 I completely renovated my house (new boiler, new lights, repaint, add more radiators, the works).

I also removed all the rads and had the boiler replaced.

Once I had re-installed all the rads (after the boiler had been replaced and the system had been shown to be working with two rads), everything seemed to be working just fine. I re-installed the rads properly (i.e. opened the bleed valves and allowed the water back in slowly to ensure that all the air was pushed out of the rad).

Recently (in the last few months), whenever the central heating starts in the morning, I hear a mysterious, unintrusive and rythmic "clonk, clonk, clonk" sound from *somewhere* in the house! It sounds like a drip but much louder. I have checked for damp patches on walls and ceilngs, but there are none. When the house is up to temperature the clonking stops. The weirdest thing is that wherever I stand in the house to listen, the clonking seems to be coming from somewhere else! It is loudest in a part of the house where there is no pipework! It is quietest in the parts of the house where there is the most pipework! I've checked all the pipework and it is bone dry.

So I am baffled. Completely! Any ideas?

 

[JohnD]

//www.diynot.com/forums/viewtopic.php?t=6026

 

[mlse]

Ok, the boiler is gas, Vaillant ecoTEC plus 418, VU GB 186/2-0

I think I've provided all the other info stipulated in the "before you ask a question" post ... this is my very first post, so please be kind!

Thanks.

 

[JohnD]

have you got thermostatic radiator valves?

what happens if you turn them all, all the way up? or all the way down?

 

[TicklyT]

Pipework makes a very good sound conductor, so it can be hard work tracing the source of the sound.

Pipes under the floor expanding as they warm up?

Plastic inserts missing from radiator brackets?

Thermostatic valve fitted the wrong way round?