In article ,
"John" writes:
A friend (as in the Flue question) has had a combi fitted upstairs (new flue
through roof). The fitter did a great job, but the electrician needs to come
in 2 weeks after my friend returns from holiday - therefore it is running
without a room stat at present.

He is concerned about the noise and some of his family have switched it off
at the spur unit. My instinct is that this is a bad idea as it could upset
the pump or fan control.

Shouldn't cause any problems -- boilers have to survive the
occasional power cut. I wouldn't switch it off this way too
often when the burners are alight though, as it may cause
localised boiling and overheating of the heat exchanger
when the pump suddenly stops.

However, what is the noise - is it a fan?

Um, how could we possibly tell?

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