"Christian McArdle" wrote in message
.. .
What do you mean that the heating "turns itself off"? Do you mean
the programmer turns the heating off and the light goes out, or
that the heating simply doesn't work?

The programmer turns the heating off , the lights on the programmer
stays on.

I'm afraid that is still ambiguous. Does the programmer show any
indication
that the heating is off, or is it just that you can't feel the radiators
getting hot?

I would not necessarily expect the programmer to know that its call for
heating is being ignored.

Christian.

All I can say is when I turn on the domestic water heating ( whilst the rads
are warming) the boiler stops and the pump stops and both lights stay on
(they stay on in normal conditions), I then turn off the domestic water
heating and the pump starts up again and the boiler fires up I.turn W.H.
off again and boiler and pump stops .turn W.H on and boiler and pump fires
up.