"Martin Evans" wrote in message
...
Hi We have oil fired boiler Camray quartet with one pump and two acl
lifestyle 2 port valves, everything has been working fine last few years
but
now boiler and pump running constantly even with programmer set to off for
both HW and CH only way I can stop running is to turn of main supply to
system. Any ideas what problem could be.


I think the controller's knackered. Probably the relay/s have welded on. I
suppose it's possible that a tank stat could give the same result but
without checking diagrams I wouldn't know. If you've got a meter can you get
it onto the terminals in the controller with the controller on and see if
the outputs are being switched. which controller is it by the way?

--
Malc