Nightmare baxi 105e

[Mbear]

Pump dia pin isn't extending, I changed dia which was worn and cleaned and lubed pin + pin seal. The odd time it did extend it would not retract when pump stopped. I'm leaning toward replacing the bypass/weep pipe (or removing and cleaning if poss) as I reckon a restriction in the pig tail pipe may cause this. Either that the whole manifold. What u thinking lads?

Money is an issue.

Which brings me to the 2nd fault on this boiler.
Another engineer told the guy the pcb was faulty and got it replaced. Same problems, basically it'll light for 30/40 secs and lockout on flame failure, working pressure ok, the board obviously didn't cure it, my initial thoughts was the pcb until he said it got changed. Continuity on rectification electrode and rectification lead.

Any thoughts?

 

[mickie]

maybe a dodgy APS and yeah it does sound like somethings blocked

 

[Mbear]

Ps when the flame failure light stays off long enough I can make the heating circulate by making pump switch, same for hw so I know the pump is working.

The aps would give a fan/flue failure light mate

 

[mattyp]

Check the low burner pressure isnt too low ! Deffo clean the weep tube and possibly replace the spindle and spring in the flow switch .

 

[Billy Bob Bob]

fault 1,have you cleaned the small hole under the pump diaphragm? very prone to causing this fault in regards to fault 2 have you checked with the combustion door off?

 

[Mbear]

fault 1,have you cleaned the small hole under the pump diaphragm? very prone to causing this fault in regards to fault 2 have you checked with the combustion door off?

I didn't have much time after I changed dia and replaced a few leaky orings.

Fault 2 would that not be a fan/flue fault in that case? Ive had it off for visual and continuity checks of rect electrode etc. but no I didn't run it with door off.

Fault 1, Is the port hole easy to clear? Is it at all likely to be a restricted bundy pipe (the one from the bypass pipe to dia section?

As I say I didnt have alot of time to spend on it at the time but it defo did puzzle me a gd bit

 

[Billy Bob Bob]

fault one port is very easy to clear you need to take the diapragm back out this is the most likely fault the bundy tube rarely blocks but can be removed quite easily with the bypass and checked for cleaning with fault 2 try it with the door off if it runs its a flue/aps/venturies fault if it does not check the burners fully cross lighting and also check the primary thermister resistance should be around 11k cold

 

[Mbear]

Cool mate. I thought I knew this chb inside out but every day is a school day.

With a bit more time I reckon I'd have sussed the flame failure fault but I think the pump dia would've still had my head scratching.

The annoying thing is that I had the bypass pipe out to replace orings and I shouldve confirmed bundy was clear whilst it was out. at least I've got something to move fwd with now b4 I go back. Ta g man

 

[Mbear]

Is there a chance the gas valve is dropping out do u think even though 240v is present?

Although it would be a bit strange that it opens on ignition only for it to fail mid operation. I think checking ntc a gd place to start with that one + running with cover off

 

[Billy Bob Bob]

Is there a chance the gas valve is dropping out do u think even though 240v is present?

Although it would be a bit strange that it opens on ignition only for it to fail mid operation. I think checking ntc a gd place to start with that one + running with cover off

it could also have a blockage but try the other two first