Potterton 40 Ignition problems

[BGK]

Fitted new Siemens 5111603 PCB 2 months ago and serviced boiler. Called back as noisy fan but all was working OK
Now there is an intermittent problem with red indicator light flashing 1/sec. 10 sec hold down gives 2 orange flashes which is Ignition failure. Boiler then relights with no problems.

Is it the fan as never been able to catch it failing to light?

 

[diamondgas]

Potterton 40 what? Sounds like a suprima maybe? Gizza clue 🙂

 

[BGK]

Duh try a Suprima

 

[diamondgas]

Has it had a new board? Is it your boiler or a customer?

 

[BGK]

My boiler, controller and service by a reg Gas Safe plumber, complete new Interpart controller and loom etc.

Just trying to understand what the best route to solve the problem as it is a strange intermittent fault, boiler working fine all day today but has locked out 7 times in last 3 days

 

[diamondgas]

They're a one for intermittent faults alas 🙂

If you're getting an ignition fault every now and again then the likely suspects are ignition electrode, spark gap, electrode lead and or connection to pcb, sticking gas valve/gas pressure. Less likely would be flueing issues, perforated flue, partially blocked heatex, those sort of things.... Really BGK you could be waiting for whatever it is to fail all together B4 you get to the bottom of the fault 🙁

 

[BGK]

I agree but going away and don't want a frozen house, not working again this morning, reset OK then locked out again after 1 hour, now OK.
Pattern is it locks out at night when only hot water being demanded.
Plumber coming today so probably start with ignition and keep going until!
Thanks for the input, I have spent my life on electrohydraulic systems hating intermittent faults, keeping a log now of when problem occurs and demands on boiler,
Ho Hum who would be an engineer in life again

 

[leedsgasservice]

Dont want to put you on the wrong track but had a similar fault a couple of years ago. The most common fault is the pcb failing but dont rule out that your pump on its way out,usually its wired through the pcb. I had one that was sticking now and again,overloading the board causing an intermitten lock out. Changed the pump and all was good. Ask your engineer to double check the pump hidden away in the airing cupboard.

 

[BGK]

Plumber changed the electrode but also the thermistor was loose not fully clipped in, may of been disturbed when checking the noisy fan?
Checked all controls, pump running correctly, diverter valve, all working as expected.
Eureka all working today so probably a electrode on it's way, let's see

 

[warrington]

Is your boiler boxed in! If it is, and not enough air circulation to cool PCB, than likely it may damaged the PCB.