Noisy radiator’s (Very strange as only three)

[martin88]

hi all,

I have recently had a new Combi boiler installed a ideal logic 30KW

Everything is ok with the exception of the three radiator’s upstairs (Landing, back bedroom and front bedroom)

When the heating is on I can hear a noise, which sounds like running water / the boiler noise coming through the radiators, this noise is the same when the heating is off but we use the hot water in the house.

I have done the following to try and get rid of the noise

1. Bleed all rads
2. Drained the system and refilled up and bleed
3. Messed around with lock shield values
4. Removed TrV heads to make sure it’s not this
5. All rads and TRV’s were replaced about 2 years ago
6. Turned pump speed down to 70% this is as low as it will go.

I just find it strange how three rads are making this sounds when the rest aren’t, below is what we have in the house.

3nr towel rads
4nr double rads
5nr single rads

Any help is greatly appreciated

Martin

 

[John D v2.0]

The mess around with the lockshield valves was that balancing them? It could be vibration through the pipe work given it happens during hot water use but it could just be too much flow through those rads. Do they heat up on the return end of the radiator a lot sooner than the other rads?

 

[martin88]

Hi John,

Regarding the mess around it’s just reducing the lock shield to restrict the flow, but if there right down or fully open doesn’t make any difference.

Yeah it’s very strange as it makes the same noise when we turn the hot water on.

We have 5 rads upstairs 1 double, 3 singles and 1 towel rad and it’s only happening to the single rads.

Im using pelger TRV’S, I thought about replacing them for the full bore Honeywell TRV’s To see if that made a difference

Thanks

 

[oilhead]

You could have a partial airlock. Try bleeding the offending rads through both the flow and return.

 

[martin88]

Hi,

I only know how to bleed rads via the bleed screw that’s on the top of rad

 

[oilhead]

Close off the return valve and bleed the rad of about 1 litre, then close off the flow valve, open the return valve and bleed again. You should get the same sort of flow out of the rad at each stage. If you don't then you know the source of your problem. When altering the lockshield, make a not of the position it is in so you can revert to that and maintain the balance of the system.

 

[martin88]

Thanks - I will try tonight, I have a feeling it’s the boiler noise passing down the pipework, I put my head on the carpet where the pipes pass beneath and I can hear the noise... the pipes pass through a brickwork wall, I’m thinking this might be to tight and that’s why I can hear the noise... maybe!!!

 

[martin88]

I have tried bleeding the the rads in questions by shutting off the valves and both sides run the same.... I’m
100% certain there is no air in the system. I think it’s boiler noise travelling through the pipework