A new Ideal Logic 18kw system boiler with Nest controls starting up randomly.

[Ray1000]

Having rectified initial wiring problems - discounted True Radiant in Nest settings by turning it off - removed an old Pipe Stat wired as a room stat - and watched the Y Plan valve seemingly working OK - the boiler still fires up when not scheduled.

It was seen yesterday with the flame icon and 61 degrees showing on the boiler screen while making the appropriate ON noise.

The temperature would change to 58 make its way up to 65 in a few seconds and the flame would go out - repeating this cycle until the fused spur was turned off.

The display temperatures seem to follow what the tank stat and the boiler temperature are set at.

Is it most likely to be a micro switch sticking on the 3 way valve ?

If so has anyone successfully freed them off ?

Thank you
Ray

 

[CBW]

Is it most likely to be a micro switch sticking on the 3 way valve ?

It could be. Do you have access to any testing equipment?

 

[Ray1000]

Thank you for the help, yes I have an electronic tester that records AC/DC voltage, Resistance & continuity. The wiring centre is a Sundial PCB variety. I fitted the Nest and with help from here sorted the original wiring problems out so I generally know where all the connections are.

It seems to be an intermittent fault ... the hot water was on between 11 & 12noon yesterday and the boiler fired up on its own around 6pm so it wasn’t a continuation of a scheduled event.