Annoying droning noise from new Worcester boiler (updated)

[emsee]

I had a new central heating system installed mid December with a Worcester Greenstar 27CDi combi boiler.

The problem I have is that there has always been quite a loud droning noise from the boiler which seems to reverberate around the house (especially in the lounge and upstairs above where the boiler is).
It is a real relief when it switches off.
It also wakes me up in the morning when it comes on.

The noise seems to be present when the boiler is operating regardless of whether the boiler is in heating or hot water mode or whether the burner is lit or not.

The boiler is mounted on my kitchen wall but the bottom quarter of the backplate is on tiles and the top three-quarters is spaced off the wall (to the thickness of the tiles).

I mentioned the noise to the installer who came out to have a look & he said it was normal and if they called out a Worcester engineer they'd "turn around and walk straight out again".
That said, I don't think I made it very clear at the time just how much the droning was reverberating around other parts of the house.

Could the gap behind the boiler be amplifying the droning noise?
Could there be a problem with the pump or fan or is this noise normal for this type of boiler?

They are coming back on Friday to upgrade a radiator which I thought was underspecified so I've asked them to have another look at it then so if it's not normal, any information that I can "pass onto" the installer would be appreciated

 

[bengasman]

As a comparison for you to illustrate how noisy these are.
I have installed one for a client in a full size cupboard in a dining room and got a call out because they thought it was not working straight away when they turned the heating on. Was only around the corner so was there 3 minutes later, only to find out client had not checked the boiler but simply could not hear it come on.

The frame (jig) should be flush against the wall over the entire height; more screws at top than at bottom so would take more load there, at least theoretically. Boiler might not be secure on the wall. If so, it could come off and cause a major gas leak.

This sounds like poor installation work. if you have any concerns that sloppy work may be unsafe, call CORGI and tell them you are worried that your boiler is unsafe and they will come out and inspect it.

 

[emsee]

Thanks bengasman, that gives me a better idea of what I should be expecting from the boiler and the installer.
The frame is secured with two screws at the top and has several metal spacers screwed to the back of the frame near the top.
I can't tell how it is secured at the bottom.

 

[Corgigrouch]

My own Greenstar 30Si is in the kitchen and is very quiet indeed though I do find that the diverter valve motor does chatter a bit when changing between modes. Not at all sure I like the idea of the way that the fixing frame is attached to the wall.. Could the noise be pipes resonating?

 

[emsee]

Could the noise be pipes resonating?

I'm pretty sure the noise is coming from the boiler itself rather than the pipes.
I insulated the pipes a few days back (which was more difficult than I expected as many of the pipes were too close to the floorboards to use the normal foam insulation so I had to use some wrap-around foil bubblewrap stuff).
Insulating them didn't make any difference to the droning noise but did eliminate the 'tap-tap' noise of the pipes expanding/contracting.

 

[bengasman]

Feel everywhere you can when the boiler is on for vibration, including the back and behind the boiler. If you find something you can feel, push against it and see if that helps. If so, wedge something in the gap as makeshift solution.

 

[emsee]

Feel everywhere you can when the boiler is on for vibration, including the back and behind the boiler. If you find something you can feel, push against it and see if that helps. If so, wedge something in the gap as makeshift solution.

I've tried that and if I push the middle of the backplate a small amount on one side towards the wall, separating it from the boiler I can reduce the droning noise slightly. I've tried jamming a small piece of foam in the gap I made but this doesn't seem to have the same effect once I release the plate.
Also, pushing on the top right front corner of the boiler seems to reduce the noise a bit too.

 

[emsee]

So basically, the consensus seems to be that it shouldn't be making so much noise and the installer should be able to do something about it?

Would putting something behind the backplate like a thick rubber mat or a thin sheet of plywood help reduce the noise or must it be mounted directly onto the wall?

I suspect they would be rather reluctant to raise the boiler up above the level of the tiles so it's flush with the wall as this would mean making a new hole for the flue.

 

[emsee]

Does anyone else have any other input I can throw at..I mean respectfully suggest to the installer when they visit tomorrow?

 

[emsee]

OK, so I had a different engineer back to upgrade the radiator & he thought the boiler was a bit louder than normal so he said he'd mention it when he got back to the office.
After a reminder from me, they arranged for a Worcester engineer to have a look which he did today.

Unfortunately, he said that that level of noise was normal and there's nothing he could do to reduce it
He did suggest enclosing it in a cupboard though.

I'm not sure where to go from here.

Maybe I'm just sensitive to the particular pitch that the pump/fan runs at.

Does anyone know what the noise level of these boilers is supposed to be? (I've got a sound meter I could borrow from work).

Would it help to put a bit of thin insulation around where the pipes come up through the floor from the boiler so they're not touching the ceiling/plasterboard? (I've already insulated most of the other pipework to prevent it touching joists & floorboards, though there are one or two points which I missed).

Would putting loft insulation down under the floorboards above the boiler help?

 

[emsee]

Can anyone help?
Or do I just have to get used to the noise?

 

[bengasman]

The boiler is poorly installed, as far as I can tell from behind my computer, that is the problem

 

[emsee]

The boiler is poorly installed, as far as I can tell from behind my computer, that is the problem

Possibly true but if the installer & Worcester engineer say the noise is normal where can I go from here?
How do I go about getting an independant viewpoint that the installer would take notice of?
I don't think the installation is particually unsafe so I'm not sure if Corgi could help

 

[mreco]

hi , i just want to add my experience, as i just had a worcester 37CDi installed (2 weeks now on a 3 bed house with micro bore pipes).
It was replacing a Hot water cylinder (boiler mate II) system and older, smaller, wall boiler.

It makes hardly ANY sound, and im someone who is 'noise' sensitive. If my eyes were shut, i honestly would struggle to know if the boilers was on or off.( and thats in the same room (kitchen) as the boiler, outside the room you'd never know). Also its not boxed in or anything

The only thing im not too happy with (ok , well the neighbours arnt) is the plumage from the exhaust, never saw any steam stuff before with the old one, now it wafts the neighbours way, and they mentioned it.
I checked with engineers and they said, itll be ALOT less fumes then the old boiler, and its mostly steam as its a condensing boiler.

Hope that helps a bit

 

[emsee]

Thanks.
Is your boiler mounted flat onto the wall?


I'm still uncertian how I can get the installer to do anything though as both they and the Worcester engineer say the noise is normal.