Hi, we are renovating and getting a zehner comfoair Q 350 (725mm w, 570mm deep, 850mm high, weighing 50kg) and planning to wall mount it - what kind of elbow room is needed for servicing? The room we are planning to put it in is 900mm wide on the wall we hope to hang it (900x1300mm room) which we've been told could be tricky to fit the bends in, but what space do we need for elbow room for servicing? Even worse we may end up digging down under it to insulate the uninsulated floor below.

We could fit in on the other wall which is 400mm ish wider, but this means having 50kg MVHR plus ducting attached to a stud wall / dry lined solid stone wall. Will it be strong enough or could we run into issues during installation or later on?

Lastly, is it right that the condensate drain needs to run at a gradual slope (ie gravity fed) or does the water get pumped out, and can this drain into a toilet cistern or internal soil pipe - or will that be horribly unpleasant? I'm not looking forward to running the condensate drain around 3 walls to get to the plumbing.

Whilst access for servicing may well not be too great, check as to what needs to be done for replacing of internal parts. I’ve vent axia sentinel kinetics, they need next to no space for routine servicing, but to do just about anything else requires the unit to be removed from the wall. Rubbish design.

Thanks everyone! We have a designer already but are trying to figure out which of two walls to put it on. Height is fine there.