Vaillant Boiler not starting Central Heating

[LanceB]

Got 240v at T4. The pump jumper was already set to 1 if im reading it correctly. the boiler is the combi version. I have 2 boilers (dont ask) both the same series but one is a combi and the other the normal version.
The pump is functioning fine when hw is drawn.

Is all this indicative of the main motherboard then or one of the others.

Thank you for all your advice so far chaps.

 

[The831Bunny]

Sounds like Mother board still. You could always swap the board from the system boiler before you commit to ordering a new one.

 

[Bunnyman]

Yep swap the mother board off ur other one, it doesn't matter that it's not a Combi it won't have the heating black switch on it but it will still work and will fit ok

 

[LanceB]

Over the next few days I will check the microswitchs as suggested and also look to swap the boards over. Fortunately the weather has improved a bit so the CH is not required quite so much at the moment.

I'll let you know the outcome. thanks for the advise to date

 

[LanceB]

Hi again
swapped boards etc over and it does appear to be the main pcb. the boards in both boilers are 130272 but previously advised to get 130331. Looking up 272 on website it suggests it is for another model boiler. will a 331work ok? They look very similar and i can get hold of one today
thanks

 

[LanceB]

My bad jts a 130273 however non issue as ive just picked up a 331 and it is exactly the same part even has 130273 printed on it!

Ill fit this afternoon

 

[Bunnyman]

If the pcb is green and has brass runners for the pcbs that slide into it then it is NOT interchangeable with the beige/white one with plastic runners! The green one is non hybrids the beige is hybrid don't try it will go bang!

 

[LanceB]

final update

replaced board and all is now well. I have learnt a few more things about my nemesis the boiler! I look forward to our next run in. Probably just as the weather turns cold.

Many thanks to all that have responded. Your advise and the fault tracking sheet for the boiler saved me quite a bit of money.

Speak next time...............