Chaps,

I've just had a call from a "frustrated" plumber. He's struggling to get a boiler to fire. He seems to think I've got the thermostat inputs crossed.

Boiler. Time clock. Wall mounted room stat in series with n/o contacts of time clock. Frost stat on a seperate input.

He's telling me the wall stat is having no effect but the frost stat will fire the boiler if turned up.

Surely I've not messed up?

S

Are the timeclock contacts made - if so you've buggered it up

If not, the plumber is just lifting the set point of the frost stat and the boiler is kicking in because it thinks the frost stat is calling

Regards

OMS

-------------------------
Failure is always an option

The time clock contacts should be made (n/c) when it's calling for heat (n/o is shelf state?).....so I've buggered it up?

Bugger!

S.

Well you have a timeclock and stat in series - both need to be made for the boiler to get a fire command - which is correct

The frost stat sits in parallel across the lot so regardless of time clock or internal stat positions, when it hits say 8c and falling, the contacts call the boiler in - this is the one th eplumber claims fires the boiler.

Regards

OMS

-------------------------
Failure is always an option

Have you followed the instructions, that perhaps contained a typo or translation error ?