BIASI GARDA HE M96

[ceskysports]

Hi ... got the dreaded green-flashing+red solid+green flashing

symptoms are:

- boiler fires up fine when CH on, gas burners fire as normal
- after 10 seconds shuts down and Lock-out comes on
- can clear lockout as normal, but when restarted only last for 10 seconds before lock out again

... it is not freezing for last week (actually quite warm ) so condensate is not frozen
... flue looks fine (and gas burn is blue/yellow) so assume no problems with flue drip back
... pump seems to be ok, as can feel vibration during 10 seconds of running time
... pressure is fine for CH (1.1 bar)

anybody knows of any other problems that this sequence of lights indicate?

cheers ceskysports

 

[Agile]

It can still be a blocked condensate drain.

This is a lack of flame detection and this can be a faulty PCB ( open circuit R39 on some pcbs ) but the registered engineer will check other things before changing it.

Tony

 

[ceskysports]

Hi Tony .. many thanks for reply

... all pipes out of boiler are clear ... and engineer "blow back" into condensate fitting and seemed happy this was not blocked .... (not sure if this is a 100% confirmation test? .. any others)

... which PCB is the most likely to be the problem ... left or right? The fuse on the right PCB is fine (some other entires suggest this is the problem)

... engineer has left, but I'm happy to remove PCB and check for dry joints.

... one other bitof diagnosis, is that both CH and DHW (with CH off) trigger the same problem .i.e. boiler fires up as normal then lock-out trips in after 5-6 seconds

cheers chris

 

[Agile]

Disconnect on test the wire to the top of the condensate trap and see if its any different.

If you have two PCBs then its an early M96 and those are less likely to fail to detect the flame but it can happen.

Check the three wires to the combustion chamber are correctly plugged together with the SAME wire colours.

Dont open the combustion area!

Tony

 

[ceskysports]

..cheers .. I will check both .. will take me 10 mins or so

.. will update when done

.. cheers again tony ... you seem more thorough my engineer that called ,o)

 

[Agile]

.. cheers again tony ... you seem more thorough my engineer that called ,o)

I have to be because if I was ever unable to diagnose the fault I would not be able to charge the diagnostic fee.

Even so an Irish lady yesterday thought our fee of £84 locally was too much!

Tony

 

[ceskysports]

) .. I can only afford beer and kisses ... I guess beer will be best currency )))))

... checked the cables (thermocouples? i assume) out of chamber .. seem fine and well ... they go to right PCB, so assume this is the ignition control PCB. Jiggled them and check there seating on PCB ... seem fine and does not solve problem

... disconnected the grey cable to the top of the plastic condensate "value-thingy" .... problem still occurs ... hmmm ... interesting. only a screw-clip, guess any backed up moisture in the trap would earth this and causes trip-out .. interesting

 

[Agile]

In that case it is likely to be the PCB.

I would be checking something inside the combustion chamber.

Which make PCB do you have?

Tony

 

[ceskysports]

,, hmmm .. bit confused?

... you say "it is likely to be the PCB", but "(you) would check something in the CB" ??

... which is it the CB sensors or the PCB?

.. the PCB is a "Bertoli Partners?" (its a 2005 boiler) ... the ? is becasue I took foto of PCB to save time and its a bit blurry when I zoom in

 

[Agile]

I cannot advise on what I would check first because it involves opening the combustion chamber and we dont give DIY advice here on gas related work.

On that PCB you can check the values of the two resistors R1 and R2 just to the left of the J5 terminal.

Tony

 

[ceskysports]

.. ahhh .. I understand ...

... I have to go now .. but I'll concentrate in the righthand PCB tonight .. I'll unclip all connectors, remove, clean and reinstate ... see it that helps, if not I check for dry joints and the R's you suggest

... thanks for all input so far .... I'll keep you posted on an successes

cheers ceskysports

 

[Agile]

You can/should measure their resistance in situ.

Unnecessarily removing components can create new faults!