Any Ideas (We need sleep!!!) noisy combi

[blackylad]

Hi all
I have a baxi 105e (installed new about 6yrs ago) which has never missed a beat. That is until british gas serviced the boiler about 6 weeks ago the boiler started to whistle loudly like a kettle. A different engineer came out and said they can't do anything until they hear the noise (quiet as a bl00dy mouse when he was here) and promptly left. We called them out again (it was getting louder!) and they put some boiler silencer in and left. Still no good. Called them out again and my wife gave a printout of this thread to the engineer //www.diynot.com/forums/viewtopic.php?t=6615
Engineer somewhat reluctantly changed the entire fitting on the hot water connection. Now the boiler still whistles but this is coupled with a noise like the loudest hoover you have ever heard!!!! Engineer number 4 comes out (always whilst i am at work and my wife has to deal with them) tinkers around and claims to have fixed the boiler. It was then quiet as a mouse. sorted? nope all he had done was to turn the temp right down on the front of the boiler so my heating was running day and night but rads were only luke warm, when i adjusted it slightly noisier then ever. Yesterday eng number5 came out and put a new thermistor on cos he thought it was over heating 4 a.m this morning sounded like a plane taking off!!! What a saga anyway long story short (a bit late i know!!!)
The boiler is massively noisy (except when an engineer is in the house)
It is a loud whistle coupled with a hoover type sound
It is seemingly only through night/ early morning
It is only when the boiler gets a bit of heat in it
It can be stopped by lowering the temp on the front of the boiler(when pilot light goes out and pump/fan are still running there is no noise)
I am a spark by trade but would like any info i can pass on to an engineer (if they blame vibration again I think I will scream!!!!)
I have a 6 month old baby who has started sleeping like a hibernating bear and now can get no sleep for the boiler (don't like to turn it off cos her bedroom gets quite cold)

 

[rojaca]

in defence of B.G I can't see how anything they would do during the service would cause the noise. Maybe adjusted the burner pressure up?
With regard to the attached thread I have to say that Boxter's additions are misleading.
I believe there was an issue some time ago but certainly not on the fibre washer for the hot water. I believe the rubber used on an o-ring inside the diverter valve was the issue. Hopefully someof the longer serving members on here will confirm this.
As for the Hoover noise. I haven't a clue

 

[plumbertemecula]

The longer the boiler remains fired up the more the noise subsides and then stops. I don't think it's the pump because that keeps running (quietly) after the boiler stuts off.

 

[Nige F]

in defence of B.G As for the Hoover noise. I haven't a clue

Defend the Indefensible Ask the American about the J.Edgar

 

[kevindgas]

I believe there was an issue some time ago but certainly not on the fibre washer for the hot water. I believe the rubber used on an o-ring inside the diverter valve was the issue.

yes you are quite right the "O" rings were a problem but this only resulted in the boiler squealling like a pig when the valve changed over a replacement sorted out the problem. haven't come across any in the last 18 months with the problem (someone will be along in no time to prove me wrong!! )

 

[Andygasman2010]

If it stops when you turn down the temp knob, it sounds like scale/sludge in the heat exchanger. Does it do it when it's cold? Or just when it gets up to temperature?

 

[blackylad]

yeah seems to be just at temp mate cos b.g have never stuck around long enough to hear the fault. However it is difficult to tell as mostly we are woken by the noise and are unsure as to how long its been on! B.g said they added boiler silencer would that not have sorted out sludge? Thanks for your time all.

 

[rojaca]

What happens when you run the hot water for a long period of time? This will get the primary heat exchanger up to temp on full load. If it is sludge in the primary it should be making a noise on dhw as well.
The pumps on these can often cause a vibration onto the casing of the boiler, which makes a loud droning noise. I've found this due to the clips above these becoming loose through excess heat, but would normally see this all the time the pump is running.
When you say they changed the dhw valve, which component exactly are you on about? There is a hydraulic inlet assembly on the right hand side, the pressure differential assembly on the left (large circular component) and the diverter valve mounted directly behind this.
Incidently if you put the boiler into dhw only mode on the selector switch does the boiler fire on its own?

 

[Andygasman2010]

I'd go for a scaled/sludged main heat exchanger, maybe a sonic clean would do it good. BG usually do these for free but they'd have to be sure it'd fix the problem first.

It's hard to say without hearing it and doing some checks personally

 

[blackylad]

O.k.
The boiler now appears to be making the noise (sporadically) when the boiler fires up , it is doing it on both HW and central heating, we got a couple of nights sleep by turning the temp gauges fairly low (below half way) but now it is happening again. The noise is definately coming from inside the inner metal protective cover which houses the burner the heat exchanger and the fan ( i think) my next question (don't shoot the spark!!!!!) is it safe to fire the boiler with this cover removed so I can pin down once and for all where this awful noise is coming from??
Cheers all
this is a nightmare!!!!!!!

 

[Andygasman2010]

It's safe to run without the white cover fitted and the controls box dropped down.

It's NOT safe to use with the silver metal cover off (the one with the sight glss fitted. It's an RGI's job to remove this.

 

[holty]

is it an instant model.the divertor had probs like this mostly on preheat.last one i did was about a year ago.