Biasi Garda M90F.32S - Intermittent fault #FIXED#

[Snier]

Hi folks,

I have a Biasi Garda M90F.32S combi which has just started to play silly beggars.
The boiler will fire up correctly and perform as normal during both CH & DHW mode but now and again it will shut itself off (no flame) while in either mode

When the boiler cuts out it tries to restart itself - sounds a bit like whirring ever second or two. It doesn't go into a standby mode and no red light appears on the control panel. Pressing the reset button does nothing - it continues whirring/pulsing every second or 2.

Last night when it cut off while only the CH was on the green operation light was flashing fast indicating a fault. Whether it was pure coincidence or not i don't know but i adjusted the temp dial for the heating and it kicked back into life and ran fine for the rest of the evening and the green light returned to normal.

This morning (DHW only) when it cut out while i was in the shower (yes i kid you not) the green operation light flashed 'normally'. I tried the temperature gauge 'trick' but it didn't help. A few mins later it started up fine and continued to work as normal during the wife's shower.

It's stated to happen on a daily basis..

If anyone has any suggestions i'd be grateful.

Thanks

 

[Agile]

You nneed to quote the actual model and serial number.

Look at the similar recent thread and you will see how I explained that it can be put into a diagnostic mode so that it gives a fault code.

Tony

 

[Snier]

Thanks Tony - will do what you say when i get home..

 

[Snier]

The model is Biasi Garda M90F.32S (47-970-22)

I have the fault finding sheet from the service manual...

"Fast pulsing operation light with lock out light Off" (As indicated when the CH was on)

Symptoms: "The burner doesn't light either in CH or DHW mode. Fan turn"

Components to check:

• Flue pipes.
  Full sequence device.
  Fan & Venturi device.
  Air pressure switch.

So i guess the question is which one of the above could malfunction intermittently...? Or be an issue when calling for DHW...?

 

[Agile]

We still need the serial number of the boiler to identify the exact variant.

All those things you listed should only be touched by a registered engineer.

Those fault finding charts are of little use to professional engineers.

Can you describe EXACTLY whet everything on the front panel shows during the fault? Also what noise it maks then!

Tony

 

[Snier]

What a knob i am..... the boiler isn't a Riva Compact which i originally posted (now edited accordingly).

It's a Biasi Garda M90F.32S (47-970-22) serial no: N015730703 GB

I now know how to get it into the service mode so the next time it plays up i'll post the fault code.

Just to add that following a cut out, as it's trying to restart there is a whirring (fan?) sound (as if it's about to fire up) that lasts about 3 seconds then it stops for 2 seconds and repeats that sequence continually. There's no ignition clicking or any other sound.

Front panel just shows a fast pulsing green light if cut out during CH mode or Green light normal flash if cut out during DHW call.

Sorry for getting the model wrong..

Just to add that I've no intention of messing with Gas/Flue stuff - Horses for courses - i'll get a qualified Engineer in. Just trying to determine whether or not it's actually worth throwing money at.

Thank you for your time - much appreciated.

 

[matt1e]

The model is Biasi Garda M90F.32S (47-970-22)


flue pipes
Full sequence ignition device.
Fan & Venturi device.
Air pressure switch.

So i guess the question is which one of the above could malfunction intermittently...? Or be an issue when calling for DHW...?

My moneys on the Full sequence ignition device.

to check turn off the power, carefully disconnect the multi plugs and take out the pcb (the right hand one)

now turn the board over and you will probably see about half a dozen dry joints (loose solder) around the relays and the half watt resistors,depending on how long they have been arcing and how much damage to the board will determine on wether you can
a)resolder the joints , if you are or know someone capable or
b)buy a new board (£95 ish)

Matt

 

[Agile]

What a knob i am..... the boiler isn't a Riva Compact which i originally posted (now edited accordingly).

It's a Biasi Garda M90F.32S (47-970-22) serial no: N015730703 GB

Thank you for your time - much appreciated.

Thats no change to your original quotation. Thats why I always ask for the actual boiler model.

Its more likely to be the ignition PCB but before replacing an expensive part an RGI would check the cheaper options.

As all the cheaper options need an RGI to check them, you might prefer to consider Matt's advice to try to resolder the connections on the ignition PCB or alternatively to take a risk and order and fit a new one.

I cannot advise anyone to do their own repairs on a PCB but many can be repaired by resoldering!

Tony

 

[Snier]

As predicted the boiler cut out again this morning.

The left and right green LED's flash simultaneously and the center red LED is lit constantly.

According to the service manual...

"Lack of burner ignition (no ignition signal from the full sequence ignition device)"

Unless advised otherwise (from the above info) I think i'll take Matt's advice on re-soldering the connections on the PCB - the cheapest option.

After reading a fair few posts you guys are rarely wrong!

I'll update this thread accordingly...

Thank you very much for the assistance Gents...

 

[Snier]

Well before having a dabble with the soldering iron i tried an old trick of applying heat to the solder joints on the underside of the PCB using a decorator's heat gun. Gotta be careful not to apply too much heat though.......

Early days, but not cut out since....

 

[matt1e]

Well before having a dabble with the soldering iron i tried an old trick of applying heat to the solder joints on the underside of the PCB using a decorator's heat gun. Gotta be careful not to apply too much heat though.......

Early days, but not cut out since....

No stop, You will damage the board even more and it isn't an "old trick"

 

[Agile]

Well before having a dabble with the soldering iron i tried an old trick of applying heat to the solder joints on the underside of the PCB using a decorator's heat gun. Gotta be careful not to apply too much heat though.......

Early days, but not cut out since....

You are very lucky not to have damaged the PCB.

Modern electronic components are very heat sensitive and any soldering has to be done quickly as well.

Tony

 

[Snier]

Yes i guess i was lucky....but i really was extremely careful in the process...

Matt - i don't want to get into an argument or sound disrespectful about the 'old trick' comment i made but a Google search will return many instances of this method being used (not specifically boiler PCBs though) - may not be the safest way and mainly it's used to remove components from PCBs - and you're quite right in your warnings - Thanks

As for the boiler.... fingers crossed it's working correctly... unsure how long for though...

Once again i thank both of you for your help in diagnosing the fault... i'd have been lost without it....

 

[binbag]

Hello
I have a similar problem. I have cured it in the past by unscrewing the little black knob on the top of the boiler and pressing the little white plastic plunger thing. this method no longer works. I now have the two flashing green lights with a red inbetween. I reset and try the boiler, it makes all the right noises, there is good sparking but no flame - then it locks out. On a Biasi Garda He, M96.28sm/d

 

[Agile]

You should not add to an existing thread and particulary when you have a different model.

The overheat stat has probably failed. As its inside the combustion chamber you need a gas engineer to replace it and check why it was tripping.

They are not intended to be repeatedly reset !

Tony