Hi Folks

I have an Ariston boiler  Microgenus 24HE MFFI model and ok, it is an old boiler but was always working fine, and it was annually serviced 6 weeks ago. Today however I got a bad surprise having an almost cold shower. Water is hardly luke. I went to see error message on display and it shows E33. Boiler still works just hot water it is suppose to provide gets luke after about 5 seconds. Any idea what is the issue and can I fix it myself?

Thanks

Ben

Hi Ben

Error E33 means Air Pressure Switch Fault. You will need to do both things first check if sth didn’t get blocked in the flue ways and fan tubes that come to Air Pressure Switch. If those two are not blocked your Air Pressure Switch will need to be replaced. If you are Gas Safe Registered you can go ahead and replace it yourself, if not I would rather advice you to call a professional help. Ariston guys are helpful and not very expensive. such check and repair won’t take more than 45 min