In article ,
Ed Sirett writes:
On Fri, 14 Nov 2008 08:31:37 -0800, RobertL wrote:

Our Vokera Maxin 24e has developed an occasional (well fairly regular in
fact) loud rattling usually when it supplies hot water. It sometimes
does is just on CH. It rattles for about 10 seconds and then the flame
goes out, then it relights and repeats. The rattling is quite loud, as
if someone is drumming on the metal case.

I guess this is a job for Vokera but I would not mind some advice on
whyether to opt for the "£160 all in fix it" or the "parts and labour"
deal.

any thoughts?

Given the symptoms you describe I'd start with the fan. Very likely it has
worn bearing and the fan is both touching its casing and ineffective.

Another thought might be a dodgy connection to the gas valve
(I don't know how relevant that might be on that boiler).
Might be able to tell if you can hear it after the fan
starts but before it tries lighting the main burner.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]