Booze and Birds

[jester119]

Now I have your attention can you please help me with a huge problem. My fiancee, new born son and I recently brought a newly renovated ground floor flat. There are a total of 5 rads throughout with everyone having a thermastatic valve (which I was told was very odd, only a few should have them.)

We have a Glow-worm combi boiler wth a central heating knob set at about 70%. When we turn the heating on they all start to get warm but after about 1/2 hour the most horendous banging sounds start, almost like a jack hammer. We have to find the rad or rads that makes the noise and turn the valve. This may stop it for 5mins but it always returns. In the end we just turn the heating off. This is'nt good though for our baby. We need to keep him warm.

I have bled all the rads and got a small amount of air out but the problem is getting us down. I dont know if it helps but the 3 other flats in the restored house also have the same problem.

I have looked for solutions and the closest I can find is perhaps The valves are faulty or incorrectly fitted!

Any response would be more than welcome. Cheers.

 

[hi-spec plumbing heating]

have you got a thermostatic valve on the rad that is in the same room as the heating wall stat ?

 

[EliteHeat]

perhaps The valves are faulty or incorrectly fitted

That would be my guess.

 

[sambotc]

Take the thermostaic head of one of the radiators and see if it happens after that.

Sam

 

[Balenza]

Jester119 wrote

everyone having a thermastatic valve

Have a look at the thermostatic valve closely and see if their is a flow directional arrow on the body and let us know what direction it is pointing towards.
A picture would be good.
This is what it may look like in the image below. I have coloured the flow direction arrow in this one white to make it more visible.

 

[namsag]

Wonder if doitall will come on with his diagrams about auto bypasses again..

Sorry jester private joke.

 

[hi-spec plumbing heating]

look at that ptfe tape all up the thread
must be a ccc job

 

[jester119]

Thanks for the responses. Erm, the combi boiler is in a seperate little room in the bathroom. The rad in there does also have a valve. I have taken that off and tried to bleed them again last nite but unfortunately it still made the noise. As for the direction, apparently they are multi directional? Im stumped!

 

[no66]

With TRV's a by-pass is sometimes needed the reason being that when all the TRV's have reached Their set max the Boiler will continue to operate if the room stat is set higher than the temp of the TRV's also the pump needs to circulate latent heat away from the boiler via a by pass.

You can create this by-pass by removing one TRV, the one nearest the room stat would be my choice.(Remove TRV and replace with standard valve)

 

[Agile]

Or you can get the same effect by just removing the TRV head!

We assume that you have got TRVs on all the rads but no bypass!

Tony

 

[ChrisR]

Which Glow-worm is it?
Any name of the trv's
Any chance of a pic?

try these:
1) When one or more of the rads is doing the woodpecker bit, try fully opening one or two others, preferably near the boiler.
That will mainly drop the Pressure , which may be the problem.

2) With the valves back in your normal positons, again wauit for the bad vibes, then try closing down the lockshield valve, That's the one at the other end of the same radiator. usually a lastic cap pulls off, to reveal a shaft with flats on it you can turn with a small spanner.
That will mainly drop the Flow through that radiator, which can also be a problem. If it seems to work, try closing all the lockshield valves down to only half a turn from fully shut, and see what happens then.

Pressure and Flow are related though!