help with a troublesome ariston

[mfgs]

I have been having some issues with a microgenus 24he. Been giving a A77 fault code intermittently, every time I go there it is fine and all the problems relating to A77 test ok. Condense clear, sensor on the recuperator giving the correct resistance. Continuity on the leads from the sensor ok. So have been at a bit of a loss as to the problem, now I am due to go back there tomorrow, but I got a call earlier to say the A77 fault has stopped and now its throwing a A01 fault, which is ignition failure. According to the customer it works first off, then when it drops out it wont come on again and goes to lockout. Does anyone have any ideas, or experienced anything similar with these boilers?

 

[R1CKY]

These have a very common fault with ignition failure. If I remember correctly they'll run for a short while, but the ignition electrodes will continuously and randomly spark and eventually lock out. Pretty much always leads to the PCB, except the one time the cause was a dirty burner, the bar that the sensing electrode was sat on was blocked and there was no flame to detect.

 

[CM25]

I've also had problems with a01 faults on quite a few of these and initially replaced electrodes etc then spoke to one of their warranty engineers after repeated probs and they go straight for the board first. Since then I've always checked electrodes for spark gap, cracks etc an as long as they look ok replace the pcb

 

[mfgs]

I went to look at the boiler today and I was there for 1 1/2 hours and it would not lock out at all. Could not see a problem with it, good spark and it was lighting up instantly. I really don't want to order a pcb without ruling out everything else. What were the symptoms when you ended up replacing the pcb?

 

[CM25]

Unfortunately my symptoms where intermittent A01 faults and I've had quite a lot. First I replaced checked replaced electrodes as precautions then spark generator and leads, then spoke to manufactures who said it's a common board fault, but since I check electrodes etc and if ok replace pcb

 

[deandive]

arrrggggghhhhhhhh ariston boilers

 

[Billy Bob Bob]

why replace the electrodes first? a continuity test normally rules them out if its continually sparking and not seeing detection then the boards shot but this faults not normally intermittent what does A77 relate to in the guide? i have also had 1 boiler with a failed pcb with this code IIRC

 

[mfgs]

I have been there again today and its working fine still.

A77 is a condense problem. Either blocked condense, failed sensor by the fan on the recuperator and some funny little pcb that is linked to the sensor on the recuperator.

It is starting to annoy me as I have never seen it go wrong so its impossible for me to say what is wrong with it. I don't just want to fit a new pcb without ruling out everything else first.

 

[Billy Bob Bob]

I have been there again today and its working fine still.

A77 is a condense problem. Either blocked condense, failed sensor by the fan on the recuperator and some funny little pcb that is linked to the sensor on the recuperator.

It is starting to annoy me as I have never seen it go wrong so its impossible for me to say what is wrong with it. I don't just want to fit a new pcb without ruling out everything else first.

IIRC,the conden pcb can be bypassed for testing purposes,you would have to speak to ariston though

 

[mfgs]

The A77 fault has stopped now it seems, the only fault they are getting is the A01 fault code. It just never goes wrong when I am there, which is incredibly frustrating.