Baxi 105e probs

[smith/jones]

Hi my 50 degree fan / flue neon began to flash on Saturday .... flue not obstructed, fan tested and works ok, had a spare pcb and fitted this........RESULT....... flame failure neon and safety thermostat neon now flashing.
The 50 degree neon has stopped?????????

Air pressure switch faulty ?????

Re fitted original pcb and the fan neon is still flashin but the flame failure and safety stat are not..........

How do i test the aps ???? i can test on pcb to see if there is power going up to it...........etc.... but at what contacts do i check on A2 block (br / b)?

what contacts do i test on the aps ?? (bk / b) ? going back to pcb...and how do i know if it is faulty or not

Any help will be appreciated as i am needing a bath now lol.[/list]

 

[ollski]

On the aps there should be markings on the microswitch of c - common, nc - normally closed and no - normally open although there are several variations. The switch should move from nc to no when the fan spins up and hey presto. The first fault you have sounds like a few board problems I have had on this model.....is your spare board a brand new one?

 

[Baxi-Remeha]

check venturi in fan for cobwebs.......have come across on with '2 strands' of cobweb blocking the air flow........

 

[mmalone]

had a problem like this on a 35/60 system boiler, they use the same pcb..

remember when fitting a new pcb you have to hold the reset for a good few seconds when first turning back on after fitting...

might not be your problem but try first !!

 

[smith/jones]

Hi i have reset the switch by turning anti clockwise and holding there for 3 secs + when i fitted the replacement board / think this is faulty.....................i have put the old pcb back and the boiler fired up and shut down after 15 secs.

Can someone explain what contacts i need to test at on the aps and where to place the probes, and what do i set the multimeter to... ?
I do know the circuit is closed and current will pass through, i have read how to do this, but am unsure about checking voltage... will wait for expert help

i dont want to make things worse

cheers

 

[B.O.B DOLE]

Hi i have reset the switch by turning anti clockwise and holding there for 3 secs + when i fitted the replacement board / think this is faulty.....................i have put the old pcb back and the boiler fired up and shut down after 15 secs.

Can someone explain what contacts i need to test at on the aps and where to place the probes, and what do i set the multimeter to... ?
I do know the circuit is closed and current will pass through, i have read how to do this, but am unsure about checking voltage... will wait for expert help

i dont want to make things worse

cheers

if the boiler fires up there is nothing wrong with the aps
i would check the flame sensor if i where you

 

[smith/jones]

Will the fan / flue neon still flash if the flame sensor was at fault, never fired up at all while i have been tryin to fix except this one time

 

[B.O.B DOLE]

Will the fan / flue neon still flash if the flame sensor was at fault, never fired up at all while i have been tryin to fix except this one time

check the flame sensor if ok go to next stage but i need to know if that sensor is ok

 

[smith/jones]

B.O.B. you got a email / msn addy m8 ?

 

[smith/jones]

Whats the best way to test the electrode that produces a small amount of current, i did put the m/mtr in amp mode, removed the F2 electrode from the pcb and put the red probe 2 this,

I then placed the com probe on the pcb board and powered the boiler / i got 0 reading on 200u...............and a (minus)003/002 reading at 20000u

Cheers, i have power at the aps, fan wants to spin on start up all the time but wont, although it did this mornin for 10 secs and then boiler shut down again

Thanks

 

[corgigazza]

I have had a few faults with the fan going to start then stopping, changed the pcb the fault went away, dont forget to also transfer extra plugs on old board to new board when swapping there may be 2 of them. Make sure you fit the correct board, use your instructions to check correct part number.

ps also check polarity