Photoresistor polarity

[JUB1L]

Can someone please indicate which way round the photoresistor should be installed on a Trianco Eurostar oil boiler with a Stirling burner assembly, The resistor is keyed to its holder, so only fits one way. The connecting plug has D shaped polarizing pins but actually fits either way!

The photoresistor has an end and side window, should the side window face the oil pump or the control unit? Once this is resolved, which way should the brown and blue lead be connected i.e. brown or blue to the top?

I cannot just try and find out which way by trial and error because the boiler has another problem which is causing lockout within a few seconds after firing up. I have to be sure the photoresistor is connected correctly before I can investigate the lockout problem elsewhere.

 

[Agile]

These are cadmium sulphide photo resistors and as such are not electrically polarised.

The sensing window needs to face the flame.

Tony

 

[JUB1L]

Thanks for the info regarding polarity. The burner nozzle is directly in front of the photoresistor so presumably the side window is for other boilers?

 

[Mike2007]

Always investigate oil flow to nozzle and oil pressure at pump first. Electrical faults are more time consuming, especially if they only occasional!
Have you checked solenoid(on pump) for a magnetic field in operation, you can do this with a light weight screwdriver?

I have a whole series of diagnostic steps if you want them??

 

[JUB1L]

Thanks Mike2007, yes I would appreciate a copy of your diagnostic steps. Can you send them to my 'personal messages' please?

 

[Mike2007]

Thanks Mike2007, yes I would appreciate a copy of your diagnostic steps. Can you send them to my 'personal messages' please?

Sent. Hope it helps.

 

[JUB1L]

Thanks Mike 2007, my messages inbox is still empty, any idea what has gone wrong?

 

[Charnwood]

A lot of forums disable PMs until a certain number of posts have been achieved. Your 9 might not be enough.

 

[Agile]

You may well need to ENABLE the PMs and from whom you can receive them yourself in your profile!

 

[JUB1L]

Thanks all, it has now arrived.