Potterton Lynx One Combi Boiler

[chornsey]

I have an old Potterton Lynx One Combi Boiler. Last year we replaced the diaphragm in the diverter valve and it has been working fine since then. However, today there was not central heating or hot water. The demand light is on but boiler is not lighting. The ignition failure light doesn't not come on. If I turn the tap on the boiler recognises this and DHW demand light comes on but does not fire up. I think I need to replace the double microswitch and lead assembly.
Is this likely to be correct?
Do I need the whole assembly or is there a cheaper microswitch I can buy?
Any ideas welcome.
many thanks

 

[Agile]

Its much more likely to be the pump proving paddle switch which is not making.

They can get gunged up and also the pump can lose its push and/or the impeller can get blocked as well.

Tony

 

[chornsey]

I know think it might be the sequence PCB as the microswitches seem ok but it just isn't even trying to ignite. Any thoughts?

 

[tryitandsee]

We have still got one of these working away. Bad press on here, but all I can say is it just keeps on going.

I assume it's the electronic.

The distribution board and the two other boards- modulator and full sequence.

The multi connection pins between the two boards to the distribution board sometimes are dodgy. Try gently pushing them back together or just try gently leaning the boards slightly to see if they connect. You may even be able to see if the pcb is arching (black burning!) as the solder joints are not connecting. I had a heating engineer resolder them five years ago, and still ok.