System boiler motorised valve fault

[gregg1908]

I recently changed a synchro motor on a system boiler motorised valve to cure a lack of heating.

All was well for a few months now when the customer calls for hot water it let's bye into the rads,am I correct to presume the motorised valve needs replacing since it has a new synchro.

 

[Simon F]

sounds like time for the new valve, or possibly some thing stuck inside, sluged up
are you sure it is passing rather than a pipe work issue causing reverse circulation
some motors are more powerful 6 watts as opposed to 5 watt, could be a factor

 

[gregg1908]

Pipe work is fine it's always worked ok you may be correct the valve or sludge I will investigate further

 

[mountainman]

Probably valve letting by. Even Honeywells, as good as they are, succumb eventually.