Baxi 100 HE ignition lockout

[bob11]

Reposting, as I didn't get any replies last time. Any ideas? Ignition pcb?.....

I have a 4-year old Baxi 100 HE, which has developed an intermittent ignition lockout problem. It always works first thing in the morning, but it may fail later in the day when it tries to restart.

It tries to ignite up to 5 times, and when it works I can hear 3 clicks (relays I guess) in quick succession within about 1 sec., the first one louder than the last two. It will then ignite about 2 secs after this. When it fails I only hear the first 2 clicks. After failing 5 times both the green power light and the red lockout light are on (neither one flashing). Sometimes it will fail after 1 or 2 attempts but then fire up on the next one.

It's on contract but because the fault is intermittent - it only fails about 1 day in 4 - the engineer can't track it down. He's checked the condensate trap and he's replaced a probe (not sure whether it's detection or spark probe).

Can anyone suggest what the problem is? If I knew what the "3rd click" was then that would tell me a lot! Thanks.

 

[baxpoti]

Temporarily remove the earth wire from the condense trap.

Does this improve the situation?

 

[bob11]

Thanks for the suggestion, baxpoti. Unfortunately that didn't improve it.

 

[Agile]

There are many components which can cause that problem, three are quite expensive parts !

The problem we have is that boilers always work fine for us when we visit.

We can disconnect the condensate electrode or even remove the condensate trap but there is little else we can do.

One possibility is the regulator on the gas valve. A clever CORGI can get an idea but if its only sticking in the morning then thats not always going to give any symptoms.

A diligent independent CORGI might change the regulator on a test basis to try to eliminate that component but you will not get that level of help from a contractor on an insurance scheme.

Tony

 

[bob11]

Thanks Tony. He's now replaced the ignition pcb. Here's hoping.....