hi could anyone help me i have an ariston micro genius 24HE MFFI and it is displaying a fault code A01
It seems to go off when the pilot light comes on for hot water

adrian, August 2008

the A01 fault code is nearly always down to the pcb, 99% of the time in fact, its a common fault, but not common enough for ariston to be responsible for boilers out of the warantee. you can normaly check this yourself, while the tap is running check if the electrodes are still sparking even after the gas had lit, this means the pcb is not detecting the flame and trying to relight. eventualy it will lock out with a A01 code, if u reset it might work for a short time but eventualy u will get to the stage where it will no longer resart.

if your handy you can replace the pcb yourself, there is someone selling them on ebay for £85 thats a steel, its half the trade price never mind retail price!

pcb part number is 65103422 just search it on ebay!

Thermo man, July 2009

HI. There was a Client with the same Problem. It was the Gasreminder! There was a little bit Gas going throuw it but not enough. Please check if the Gaspressure behing it is strong enough. Andy

PS: Had another Client with Vaillant Therm, it was the same Problem. Good luck

Andy, November 2008

i am an engineer for ariston mts group. your problem will be possible faulty pcb. symtoms ... burner ignites and a spark can still be seen across electrodes by looking through sight glass..

daz, September 2008

We have exactly the same problem.... in process of trying to get someone to look at it. We were away for a week and when we came back it didnt work.
Have you had it fixed??

Nicola, September 2008