baxi 105 he fan fault

[REDSAW]

fault light for fan comes on and locks out!.

checked the ventury, took the flue apart, checked continuity of fan and aps wires, fan runs strong when running, changed the APS then nothing!. put the old aps back in and the fan ran at full speed but did not ignite boiler.
took the old aps out then put the new one back on and it ran fault less!!.
left the job yesterday and the tenant called to say it has locked out again!:/

the sequence goes to flicking the fan momentarily on and off for 1 second then eventually locks out?

i have done this twice now and left it running so the fault will be the same...fan fault indicator, please re read from the start................****!:sosp:

always happens to make you look an idiot in front of a new client with 200 propertiesrrr:

any one had this before as i am stumped?

i think mark is too?

ps. me thinking, could this be a relay on the board or a dry solder...broken harness?????

 

[Jimbob]

Iv had this as it's whittled down to faulty PCB... Hard to diagnose though!

 

[Billy Bob Bob]

it is looking like a pcb martin now as you tried everything i suggested if you were closer i could lend you one for testing,i would also carefully check the pins on the pcb plug of the aps circuit they can pull out also continuity test the cables before looking at pcb

 

[Ermintrude]

Fan relay has died on pcb. Where are u?

 

[REDSAW]

in nottingham,

i gave the connector blocks a wiggle and they were firm, i also tested continuity from aps to pcb pins think i did fan as well?

tell you what it reminds me of, car indicator lights sometimes dont blink then there ok again resulting in sticking relay!!

 

[REDSAW]

do you think this is the same fault!!!!?

http://www.ukplumbersforums.co.uk/g...umbers-only-private/28660-105e-fan-fault.html

 

[Billy Bob Bob]

do you think this is the same fault!!!!?

http://www.ukplumbersforums.co.uk/g...umbers-only-private/28660-105e-fan-fault.html

yes but whats causing you issues in this case is yours is a HE version and we know they eat aps ,pcb is looking like the issue

 

[Ermintrude]

Sounds like it. Common fault up here

 

[Ermintrude]

Conny terminals not shorting out / causing lock out??

 

[REDSAW]

i will have a look at those tomorrow,
going to pull the board and check leads con pins and solders

 

[diamondgas]

It isn't a student drying their knickers on the flue outlet is it?

had a fan running slow the other day .. Produced 1mbar across the venturi, sometimes would, sometimes wouldn't flick the aps! I think a good fan gives about 4mbar? Not sure exactly but it's something worth checking if you know what it should be producing ..

I wish I was more observent these days and wrote things down!!!

 

[REDSAW]

just got back from there.

put a new pcb in and no change!

put the old one back in grabbed hold of the aps and re positioned it as it is loose at the back of the fan (fed up taking it in and out) and it fired up straight away!!!!
the leads all have continuity and are fitted tight, it has also been fitted properly to the casing prior too.??/

i did notice that the clear tube had water in it and there was about a thimble full, thats not normal is it?

left working at least for now.

 

[diamondgas]

What a pizzer Has to be fan or flueways/secondary hex/condensate backing up kind of thing?

 

[Billy Bob Bob]

just got back from there.

put a new pcb in and no change!

put the old one back in grabbed hold of the aps and re positioned it as it is loose at the back of the fan (fed up taking it in and out) and it fired up straight away!!!!
the leads all have continuity and are fitted tight, it has also been fitted properly to the casing prior too.??/

i did notice that the clear tube had water in it and there was about a thimble full, thats not normal is it?

left working at least for now.

no its not normal to have water in the tubes ,but from what you said the other day you have had the flue out and all seals are good?

 

[REDSAW]

took the elbow off and remade joint, this was bone dry inside so was the fan and connector.
boiler has not obviously been working for a couple of days!.

boiler would still work without flue elbow connected? as i tried that and the same-didnt work