MVHR Ducting and Grilles

Tifosi

I have recently received a number of scheme proposals for a MVHR system and I have a few queries in regards to the ducting and in particular the placement of the grills. I am hoping for advice and experience of others that have MVHR systems installed or reviewing installation at present.

From what I can gleam from a number of vendors the desire is to locate the supply terminal at least mid-way into the room and 1.00m away from the wall. Terminal to be away from the bedhead. Not really a fan of wall mounted vents and using the coanda effect(don’t like the terminal).

Extract via an undercut on the door between 10-15mm. Is anyone using the transfer gap at the head of the door architrave for extract and/or installed the supply at low level within the wall.

Ducting “semi-rigid” appears to be favoured by some and appears to have come a long way since flexible ducting, should I still be considering galvanised.

I assume if feasible, it is more desirable to install separate ducting to central manifolds for supply and extract and thus eliminate any crosstalk, is there any other benefits, easier to balance maybe ?.

Anything else that I should be reviewing, grateful for any input.

MicktheMan

If possible run all ducting within the thermal envelope. If any of the ducting is outside the thermal envelope (e.g. in cold attic space) then make sure it is suitably and well insulated.

Design duct layout to reduce as much as possible the amount of ducting required.

Link unit power to smoke alarm so that if the alarm is activated, power is cut to the unit.

Tifosi

Ok I am progressing the MVHR and I am back to the wall mounted supply air terminals, which I previously stated I dislike. Has anyone installed these terminals or been in a house with them installed, I am looking for feedback.