Install the app
How to install the app on iOS

Follow along with the video below to see how to install our site as a web app on your home screen.

Note: This feature may not be available in some browsers.

Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws

mfgs

Plumbers Arms member
Plumber
Gas Engineer
Dec 15, 2010
3,460
1,178
113
I have got to look at a ariston microgenus 32he tomorrow with an intermittent e34 fault, I think the customer said. I looked it up and it says air pressure switch problem, was wondering if there are any common problems with these and I have only ever seen about two of them before.
 
Check hose from fan to aps, might have water blocking it inside and aps won't make. Had this a few times.
 
it will either be dirt in the fan venturie,water in the hose,the ring in the secondary condensing hex(in the flue spigot on early models) or just for a change the aps but you can verify 3 of these without parts
 
its the restrictor ring between the fan and the flue , take that out, and it will take care of E34. I had a similar problem, tried changing the aps didn't work, did some more googling and found out its the restrictor ring.
 
Spoke to ariston who said most of the time the fan is at fault. Said resistance needs to be between 40-45 ohms across the windings and differential pressure at test point above APS on top of boiler no less than -0.6mb. I got 24ohms resistance and -0.55mb differential pressure so ordered up a fan, got to fit it next week. Checked the tube to the APS and all ok, flue clear etc. Lets hope the fan cures it. Apparently the heat in the boiler affects the fan and makes it run slow and the APS drops out, normally happens when hot water has been run for quite a while which the customer confirmed as it only looks out when running a bath or in the shower.
 
Last edited:
  • Like
Reactions: 1 person
Yeah fitted a new fan and I haven't had a call back to say its locked out since
 

Official Sponsors of Plumbers Talk

Similar plumbing topics

We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.