While you wait for answers, we may have found some information which could help you.
Click here for Boiler Reset Button Hoterror code e02 wont work when pressurised?
Why does my boiler remain ON - even when switch is moved to OFF?
No display on Ariston e-combi approx3yrs old?
What is the problem?
I have an Ariston Clas He system with an error code of 1P2?
Ariston Microgenus 23 MFFI PCB Defect?