fan wheel makes noise in combi boiler - worcester 28i junior

[dandt]

Ive fixed the above problem but would like some advice...
Anyway yesterday boiler started making a very fast clicking sound.
On opening things up I discovered it was the very fast spinning fan wheel.
The wheel and its power supply/solenoid are fixed by 3 bolts each of which goes through a rubber plug before screwing into bottom of flume [please forgive any inaccurate vocabulary]. There is also 'W' shaped bracket with a rubber plug which pushes up against the fan unit. I noticed that by changing the position of the wheel ever so slightly the noise disappeared - there had obviously been some friction / rubbing somewhere inside. I have been assured by helpline that it is still safe and that if the fan couldn't operate the boiler would simply cut out. Three questions..
1. Is it designed to deliberately have some give/free play? eg the bolts are narrower than the inside of their plugs. I assume if the thing were fixed absolutely rigid the speed of the fan wheel would cause vibrations and damage elsewhere.
2. Why has it been designed with so little tollerance regarding free spinning versus friction. Its ok now (and this is the first problem in nearly 2 yrs) but is the thing going to gradually work itself out of position again.
3. Is this sort of thing a common problem?

 

[Agile]

Unfortunately you are taking a much more detailed interest in a single boiler component than is economically justified.

To a boiler engineer the simple solution if a component is not functioning properly is to just change it.

Furthermore as the fan is part of the gas train and combustion process its normally only a competent CORGI registered person who should be working on it.

Worcester fans seem to be slightly more unreliable than other makes but are also rather cheaper too.

I find your posting rather different to follow but in the generality boiler fans do operate reliably in a hostile environment for a long time.

Tony Glazier

 

[kevplumb]

Furthermore as the fan is part of the gas train

the fan is part of the flue system!
MR MOD 10

if you want me to shut up shut the pratt up who is doing the hachet job on me in the combustion chamber
and keep deleting and i will keep editing

 

[dandt]

thankyou for your reply Agile
Yes it is a throwaway society!
I have probably saved myself a large callout fee plus the cost of replacing a whole part. It may well be economical for you to change the whole thing.
Furthermore if I hadnt investigated, it would be very easy (given the horrible noise) for a rogue trader to sigh and tell me the whole boiler needed replacing - this comment is not aimed at you. But I am glad I had a look myself.
Finally what is wrong with being interested?
There is plenty I have learned in recent years which has proved economical.
If anyone can answer my first two questions I would still like to know
Thankyou

 

[kevplumb]

1 yes

2 possibly but it shouldnt

3 it (like a lot of things) happens

 

[dandt]

thanks for reply