'Lock Out' LED fault on SIME 30he

[mattdog82]

Hello, last night my sime packed in once again. This time a red light appears on the boiler which is referrred to as a 'lock out' fault by the manual.

When the boiler atempts to fire, I can here the gas valve pulsing and can hear the fan running. The only thing I am unsure about is the electrode as I can not see if it sparking or not. When I remove the electrode I can get a hight resistance between the lug end and the probe, but I also get a resistance between the probe and ground. Is this correct?????

I also checked the resistance on the transformer which seemed ok and I have 70v centre tapped coming from the pcb.

New electrode reccomended???
Cheers
Matt

 

[bengasman]

After opening the combustion chamber, a visit of a RGI is recommended.

 

[mattdog82]

Ok changed the electrode and no spark. I am thinking the Ignition transformer next??

 

[bengasman]

An experienced brake down specialist will work safer, quicker and probably cheaper in the end.
Randomly replacing parts in the hope that it will come back to life is usually a slow and expensive way of doing things.

 

[hansthebear]

could be an interference issue if the room stat wiring isnt insulated all the way to the point of connection, will also have this fault if the flue is undersized

 

[mattdog82]

Cheers for the reply.

I do not have a room thermostat wired in.

Also I got the voltage wrong the board. Its 155vac either side to earth. The ignition transformer is reading a resistance of 0.002 ohm.

 

[mattdog82]

Oh and Bengasman. I will be taking your advice very shortly.