Potterton Suprima 80 HE keeps shutting down - completely / indicator lights off

[PDUK]

Hi

I have a strange fault with my boiler and I can't figure out what is going on...

I have a Potterton Suprima 80 HE approx 6 years old and I haven't had any major issue until now.
Two days ago it stopped working, the indicator lights were all off. Previously when this boiler had the occasional blip and lockout it would indicate an issue with a red flashing light which I could clear by resetting the boiler. But this latest issue could only be cleared by switching the fused switch for the boiler off and waiting an hour and switching it on again. The boiler would then fire up, green indicator lights come on as normal and provide heating as normal for a few hours before it completely shutting down again.

I worked through the following checks:

• Checked that the pump is working and sounded like normal
• Checked the expansion tank and made sure nothing was blocking the flow
• Checked that the valve near the hot water tank is working
• Bled the radiators and fairly sure we don't have an airlock
• All radiators would warm up as normal and hot water is ok
• Flue isn't obstructed
• Listened for the fan in the boiler and I could hear that working
• Timer and room thermostat set correctly and seem to be in good working order

All of that seemed ok.

After reading around it seems that it is not uncommon for the PCBs to go faulty, so I removed and inspected the PCB and it looked looked like new, no black / scorch marks as people seem to often report, solder joints clean and solid.

So I came to the conclusion that one of the PCB components have become faulty.
However while the boiler was in shutdown mode and before I went to switch off the fused switch I accidentally disconnected one of the connector blocks on the PCB and the boiler switched on with green indicator lights. It was the connector block which has live neutral and earth wires only and leads to the gas valve.

While the boiler did switch on, it was unable to switch on the burner which I presume is because I disconnected the power/control to the gas valve.

It made me wonder if it is after all a fault on the PCB or is the gas valve faulty?
The PCB is a Honeywell code 5110550.07 manufactured May/09

Any advice would be much appreciated!

 

[Chalked]

Please read the forum rules, as for giving advice to non gas safe registered installers.
You are clutching at straws, without the correct flue gas analysers, and knowledge of boiler workings.
Please ring a registered gas safe engineer. Much better and safer in the long run.

 

[PDUK]

I don't really understand the issue with my post.

I'm attempting to see if it is likely to be the PCB, if so I can easily switch it out myself. It is very easy and low risk.
If it is the gas valve then clearly I don't want to touch that and I will get a gas safe registered installer to fix.

 

[Dotty]

You need to be a gsr to work on all aspects of the boiler. You are not qualified to even remove the case.

Call in a gsr. The boiler will need to be checked after any work done to it.

That simple enough for you?