POTTERTON SUPRIMA BOILER AMBER LIGHT NO HEATING!

[kadis9969]

I have a suprima. When I put heating on the boiler will show a solid amber coloured light and not fire up. When I put the hot water on the boiler fires up like normal and displays the green light. When I put both on them on the boiler fires up and works like normal and displays a flashing light from green to amber. Heating still does not work. Is this the PCB that has gone?

 

[holty]

could be room stat

 

[spudkey]

sound like a faulty motorised valve rather than boiler

 

[kadis9969]

how do you test a 3 port motorised valve?

 

[MANDATE]

Should be able to remove the head off the spindle, then observe the 'D' shaped hole as you try the three different positions.
You may find it only gets HW position and mid point position and never gets to CH position. (motor problem) Or you may find it does go to the CH position but fails to fire the boiler due to faulty microswitch.This is supposed to make the orange wire 'live' with CH only selected.
If it reaches mid point, you can rest assured the room stat is ok, it needs the power supplied by room stat to feed the white wire of valve to drive motor over first half of travel and to arrest it in that position.