In message , "Dave Plowman (News)"
writes
In article ,
Nigel Hewer wrote:
I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.

Do you mean when the boiler is switched off by the programmer? Older
systems will often have the pump running while the boiler cycles. On those
the two aren't really interdependent - the pump is controlled by the room
stat while the boiler by its own.

Does anyone know, if I purchase a new programmer, if this has the pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.

Pump overrun devices are usually part of the boiler rather than programmer.

Of course Servowarm tended to have a mind of their own. ;-)

I'm just wondering if his timer is a Horstman 424 - one version of which
(the emerald?) had a bimetalic pump overrun integrated into it

OP - you are just going to have to dig in a bit deeper and have a look


--
geoff