Noisy hissing radiators hissing noise in new rads or trv's

[dmdm272]

Hi, I've done a search and read some around the subject but unsure how to proceed. We've just had a new boiler and new rads fitted (except one in the bedroom which was already newly fitted within the year).

The new rads, especially a vertical one in lounge and towel rail in bathroom all make a noise when heating. It sounds like a hissing noise or like a kettle before it boils or a faint version of a toilet cistern refilling. It is loud enough to be noticeable and we don't want to live with it.

Some have suggested rads need bleeding but our installer doesn't seem to think so, sure he would do it if required as it would be an easy fix.

Some have suggested trying a different brand of trv- is this the case, should we try a different one and see how it sounds? I do think the different one in the bedroom sounds less noisy.

Thinking of the kettle/boiling pan analogy could it be like the tiny bubbles of gas that appear which will leave the system over time when the sentinel takes effect?

Is there anything else we can try?

Many thanks for any help.

 

[twgas]

Possibly the pump speed too high, or lockshields turned too low

 

[JohnD]

If you are next to a radiator and it is hissing, does it stop for a few minutes if you turn the radiator knob slightly up, or slightly down?

 

[dmdm272]

Twgas: thanks. I will ask my installer about this.

JohnD: if the trv is turned so that the radiator shuts down then the noise stops yes. So it makes noise when rad is "on" but not "off".

I've asked the installer to try another brand of trv. He says on he will do but he used Drayton RT212 which are a good brand. Anyone have any experience/problems with these?

Any recommendations for trv's?

Thanks again

 

[JohnD]

but does the noise stop if you turn it higher?

 

[dmdm272]

Hi John, no it doesn't stop if you turn it higher. It makes the noise until it is up to heat anf only stops if the rad stops, if the rad is continuing to be hot the noise remains.

 

[D_Hailsham]

Which boiler did you have fitted - make and model no?

Does the noise happen all the time?

If not when? e.g when the room is up to temperature.

Did the installer balance the system? If you don't know, or are unsure, ask him.

Does the noise go away if you remove the TRV head?

 

[dmdm272]

It seems a lot better now we swopped to honeywell trv's. There are still a few trickling noises but no/much less hissing.