Baxi Bermuda........mind of its own !!

[Bandsman]

Davebgas,

Yes you are correct on all points, to get the hot water heating to stop when its having one of its funny turns you have to turn the stat to max! But if the heating has not been on the cylinder stat works normally!

Please see my reply regarding the missing? contact pin on the timer.
Thanks

 

[Bandsman]

Terminal 1 is marked "On" and Terminal 4 is "Com" nothing for 2 or 3.
Thanks

 

[D_Hailsham]

Terminal 1 is marked "On" and Terminal 4 is "Com" nothing for 2 or 3.

Terminals 2 and 3 do nothing on a SM300, so I don't know why there is a link from N to 2.
The link between L and 4 is correct. When the timer is ON, the switch closes joining terminals 1 and 4, which supplies electricity to the black/red wire. It's now a case of finding what that wire connects to at the other end.

Are you sure there is no other wire connected to terminal 2.

You mentioned a cylinder thermostat. Are you talking about a stat fixed to the side of the cylinder, about 12 inches up, usually with a length of curtain wire round the tank?

How many motorized valves do you have? Makes and model no's please.

Which make/model room thermostat do you have?

 

[Bandsman]

Thanks,

Positive nothing else on terminal 2. Yes I do mean the stat on the cylinder and the room thermostat is a Drayton, cant see a model number on it. For anything else I'll have to move the TV (and the Children in front of it) and get back to you another day.
Thanks very much for helping and as soon as I have the info I'll post it.
Thanks again
Mike