Ideal Mini C32 ignition problem

[Terrier67]

Please can anyone help with an intermittent fault on Ideal Mini C32 combi boiler.
When heating or hot water is requested, the boiler always 'runs' and you hear an ignition click, however it either;
a) doesn't ignite and goes into fault mode
b) initially ignites for a couple of minutes but then goes out almost as though there is insufficient gas pressure.
Frustratingly the boiler will work trouble free for a week or so, then start acting up again and seems to be most 'vulnerable' first thing in a morning!
The plumber who fitted the boiler in 2005 has changed some sort of control switch and the main PCB but to no avail and now says he can't help any further.

Any bright ideas welcome

Thanks in advance.

 

[transam]

main pcb ?? there are 2 on this model (?) control board & ign board ?

there are also diagnostic lights , on veiw may be ? which should tell or indicate something ??

 

[Agile]

If the red ignition lockout light is not coming on then its most likely the pump proving switch is not being actuated reliably.

You mention "going into fault mode"! Unless you can explain what you mean in detail then I cannot help any further.

Tony Glazier

 

[Terrier67]

He replaced the main PCB (Logic BI1475 116), not the ignition one.

The only visible diagonstic light is the left most LED from the PCB that starts to flash rapidly when faulty.
The user guide says this means either empty primary circuit, no primary circuit flow, no boiler ignition, excessive temp in primary circuit, or faulty temp probe.

Once again, thank you for your replies

 

[Agile]

You need to look at book and put boiler into diagnostic mode either permanently or for a test.

You can drill carefully (!) 2 mm holes to be able to see the three leds. Then move the back link from 2-3 onto 3-4.

Then see what the boiler thinks is wrong.

There is another recent thread about a similar fault but as he thinks he knows more than I do about boilers, I have stopped helping him.

Tony