Baxi 80e combi problem

[bennythedip]

Hey all,
Had a problem with the boiler sequence starting so pump runs, fan runs and aps clicks. Fan was then shutting off and flame sensing light illuminated even though it didn't spark and no flame and no warning lights. The aps seemed a bit ropey so I replaced it. Boiler fired up first time so I put all covers etc back on and tried it just before I left, same as before. Reset it, no good covers off. Tried resetting a few times, but sequence the same, would run until fan runs for a second then cuts out and flame sense light illuminated and just sits there. Tried resetting couple of times then it fired and ran. Tried a few times and fired every time. Covers on and tried again few times and fired every time. Just got call to say it's back doing same thing, anyone any ideas? Any help appreciated as heads a bit fried now!

 

[Alpha man]

Flue Venturi or PCB?

 

[bennythedip]

I rang Baxi technical and he went through checking aps and checking voltage to fan and both were ok. He seemed to run out of ideas at that and said it's probably the pcb. I'm just not 100% convinced that it's the pcb. If I order it and have it installed before Christmas and then it doesn't work I won't be the most popular of people!! Anyone any other ideas??

 

[Subby]

Usually if there is a wierd problem with a boiler and the display is the PCB

 

[Billy Bob Bob]

I rang Baxi technical and he went through checking aps and checking voltage to fan and both were ok. He seemed to run out of ideas at that and said it's probably the pcb. I'm just not 100% convinced that it's the pcb. If I order it and have it installed before Christmas and then it doesn't work I won't be the most popular of people!! Anyone any other ideas??

Remove the fan,venturie may be melted, fan relay in the pcb failed,if its not i would still be looking at the pcb

 

[bennythedip]

The pressure going into aps seems good and you can hear the click from it but as soon as you hear the click that's when fan shuts off. It's as if the pcb is reading the feedback from aps as not making even though it is.

 

[markadams]

Have you checked the wiring from the APS to the PCB? maybe a broken wire making partial contact or a dirty contact.

 

[Last Plumber]

I may be wrong here because it is a while since i worked on those.
As with most boilers they start on low fire but I cannot remember if the fan drops to a low speed just as it gets to ignition, ask tech if it does that !

 

[bennythedip]

Have you checked the wiring from the APS to the PCB? maybe a broken wire making partial contact or a dirty contact.

Yea have checked the continuity and it's ok

 

[Gary80gas]

What did Baxi tech give as explanation for flame light coming on with no flame? PCB?

 

[bennythedip]

Yea, he said it was probably the pcb but didn't sound overly confident. I'm going to change it someday this week and I'll post how I get on

 

[Leo21]

It's the pcb.

 

[bennythedip]

Changed pcb today and all's good. I'm always nervous putting in a pcb when it's a fault like this as I never feel 100% confident unless the old one has completely gone bang. I wouldn't think that there's too much wrong with the old board, is there anywhere you can send them to be refurbished? Would it be worth it? Thanks for all the help as always!

 

[Leo21]

Just bin it. Well done by the way, it's always a leap of faith fitting a pcb.