high pitched squeal when heating is on

[pinksgem]

on tuesday 25/1/05 my boiler (vaillant combi boiler just over a year old)
started to make a high pitched squeal / noise only when the heating is on, so i bled all radiators no air in any of them. Only way to stop this noise is to turn the heating off and then run a tap for about a minute any ideas please

 

[PEDANTICVINDICTIVEMAN]

Perhaps you have a pig stuck inside the casing, it'll be the same pig you see flying when you get someone who knows what their on with to fix it.

 

[wilhelm]

bad day?

 

[Min]

This happened with our boiler at work. Squeeling pig stopped when hot water tap open. Turned out to be a fault in the boiler that needed fixing.

But perhaps yours is different....