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Sorry if the answer is elsewhere - couldn't find anything with a quick search.

Awoke last night to hear cent. heating pump running (should have gone off hours before)

Stripped down timer and cannot see anything wrong with micr switch or heating switch (it is a Randall 102). timer itself is running correctly but turning the "water only/off/heat & water" switch made no difference, nor did operating the thumbwheel - the pump was still running.

Had a look in boiler (Maxol Morocco 30) expecting there to be a PCB or something which could be acting up, but theres not a lot to see TBH.

Only thing I can see which seems to control pump at all is the ""pump overrun thermostat"

Could this be the problem?

If so where can one be sourced?

I should say that for a while now the pump hasn't always stopped smoothly (for want of a better description), it sometimes "surges" to a stop, occasionally kicking back in 3 or 4 times before finally stopping.

Many thanks for any pointers that anyone can give.

A boiler interlock would turn it off

[quote="Cav"]A boiler interlock would turn it off[/quote]

Is this something that can be added?

Its done the same thing yesterday, 1st time as far as I know, since the original post.

Was running about 2 hours after timer had turned off - would have thought pump got its power feed via timer?

[quote="Passmethehammer"][quote="Cav"]A boiler interlock would turn it off[/quote]

Is this something that can be added?

Its done the same thing yesterday, 1st time as far as I know, since the original post.

Was running about 2 hours after timer had turned off - would have thought pump got its power feed via timer?[/quote]

I have the same problem "pump doesnt shut off when CH & HW off". Could this be that there is a fault with the motorised valve micro swith ?
Or do you think it is a programer fault.