Combi boiler making screaching noise when in DWH mode

[Marty32]

Hi folks

When the DWH is running on my combi boiler it screeches until I turn the taps off. It seems to be louder at the boiler (boiler is in the upstairs bedroom where the DHW cylinder used to be) and up until a year ago didn't make this noise.

Is it wear and tear, water pressure or both?

Cheers folks

Mart

 

[diamondgas]

Make/model of boiler Mart?

Does the water still get as hot?

 

[Marty32]

It does mate yeah - sometimes too hot so been turning the water temp down which sort of works...

 

[Marty32]

Sorry I can't remember but think its a baxi?

 

[diamondgas]

Sorry I can't remember but think its a baxi?

Why don't you have a look?:thinking:

 

[Marty32]

lol sorry pal its not me being lazy I'm not at home at the moment but when I get home I'll post it on the forum. I just thought this may have been a generic problem that happens to boilers etc?

Thanks again

 

[diamondgas]

lol sorry pal its not me being lazy I'm not at home at the moment..

lol ... Well I did wonder... 🙂

Hi pitched screetching could be hydralic or heat related. When you get home turn the boiler off and run a hot tap. If the noise is present with the boiler electrics switched off it's hydralic if not it's heat related. Kind of points us in the right direction to look... Make and model will let us know if it's acommon fault on that particular model or not ...

 

[Marty32]

brilliant diamondgas I'll do that and then post on here when I know what make and model is!

Cheers mate

 

[Billy Bob Bob]

how much do you want to bet its a 105 instant????????

 

[diamondgas]

how much do you want to bet its a 105 instant????????

Actually I'm thinking "It's twenty to eight, this bloke works late!!!" LOL

 

[pobsdad]

Sweepstake,anyone?
I'll go for Baxi Eco.

 

[Marty32]

Lol sorry guys its actually Biasi combi boiler (not condensing) so obviously created sweep stake excitement over nothing!

No idea what the model is but its been in for a good 6 - 8 years

 

[diamondgas]

Lol sorry guys its actually Biasi combi boiler (not condensing) so obviously created sweep stake excitement over nothing!

No idea what the model is but its been in for a good 6 - 8 years

And?

Is the screaching heat or hydraulic related ?

A Biasi eh!:59:

 

[Marty32]

Yeah might help if I said! It's hydraulic for sure

 

[weseeyou]

My boiler has started to do the same thing. Its been getting very hot lately and tripping the over-heat stat.

When I run the hot tap the boiler immediately starts to bang really loudly . I've stripped it to give it a really good cleanout and found the diverter valve and bypass are both clogged with scale . i reckon the recent extreme heat has caused a lot of limescale to become detached which has blocked the primary and secndary heat exchangers and the diverter valve to say nothing of the rads and pipework.

if you are in a hard water area and have no water softener or additive in your system you might need a power flush. They ain't cheap ! I was quoted £250.00 for 9 rads

 

[PlumbBobBob]

that sounds quite cheap for 9 rads.

 

[diamondgas]

Yeah might help if I said! It's hydraulic for sure

Are you in a 'hard water' area as 'weseeyou' suggests? You'll know coz your kettle will get caked with white 'stuff'! It could also be the filter on the cold water supply! Had any work done on the outside mains recently?

I think you need to get GSR engineer out Mart ... It sounds like the flow of water through your boiler is being restricted somewhat!

 

[Marty32]

I believe I am in a hard water area and suspected it could be limescale etc. Not sure about any water mains work as such but it cut off due to a burst main a couple times so could this be the prob i.e. a filter etc?

I'm gonna pretend to myself that I'm GSR and pull the boiler apart and see if I can fix it... its been nice knowing you guys.. BOOOM!

Just kidding I'll get someout if necessary Diamond

Thanks again for all you guys replies!

 

[diamondgas]

I believe I am in a hard water area and suspected it could be limescale etc. Not sure about any water mains work as such but it cut off due to a burst main a couple times so could this be the prob i.e. a filter etc?

I'm gonna pretend to myself that I'm GSR and pull the boiler apart and see if I can fix it... its been nice knowing you guys.. BOOOM!

Just kidding I'll get someout if necessary Diamond

Thanks again for all you guys replies!

Hopefully it's the filter rather than lime scale! Check out if you are in a hard water area and get a limescale filter fitted mate! It'll save you a fortune in plumbing repairs and kettles!!!

 

[Marty32]

Sorry if this a silly question but do you mean the filter within the boiler? I can install a lime scale filter if its something that goes on to the mains inside the house or does it need a magna for the boiler?

 

[diamondgas]

Sorry if this a silly question but do you mean the filter within the boiler? I can install a lime scale filter if its something that goes on to the mains inside the house or does it need a magna for the boiler?

I meant the filter in the boiler cold supply Mart!

Regards the limescale filter, check around your cold water mains stopcock. That's the usual place to look for a limescale filter. That's if you are in a hard water area! You'll not need one if you aren't!