Central heating always on...

[malefic]

We have just got back from a couple of days away and we have found the CH is constantly on, even though its switched off on the timer!

Switched it off at the mains and everything stops, switch it back on again and the flame start up and the central heating is on again.

I have 4 settings on the timer:

OFF - should switch off the CH timer
ON - always on
ONCE - timed once a day switch on
TWICE - timed switch on twice a day

Its currently sat in the OFF position and the CH is on again!
I flick through all the settings and nothing happens.

Any ideas before I get on the phone to someone?

The boiler is a 14 year old Worcester boiler if that changes anything.

Think what I am looking for is an answer to the 'is the boiler faulty or the timer switch gone haywire?'

Cheers
Ry

 

[doitall]

Frost stat, or stuck MV microswitch.

 

[malefic]

Anything 'doable' by a numpty like me or is it a BG call?

 

[mickyg]

have you got BG cover? if so call em, thats what you pay for.

 

[doitall]

You could tell us what controls you have and the type of motorizes valve for starters.

Have you got a multimeter.