Rich97941

I'll be adding AC to an MVHR system. Although they do different things, I wondered if it was important to ensure that the MVHR didn't waste that expensive cool air and was thinking of a sort of reverse summer bypass so that when the AC was operational the MVHR would recirculate existing air rather than bring fresh hot air into the house. I had envisaged a simple valve arrangement that connected the outside supply and exhaust air ducts and blocked fresh supply. The control system would restore "normal" mvhr opeation in the the event of a boost demand due to high humidity etc. Has anyone done anything similar?

When installing a MVHR, most of the examples and instructions seem to indicate that a direct route through the nearest wall is the best option. I'd be happier if I could vent through the eaves of our bungalow as they are relatively easy to get to, made of wood and the vent covers would be less visible. The pipe run to the MVHR would be around 3m in an inverted U shape passing through the loft so outside the vapour barrier but insulated with 250mm fibreglass over epp ducting. Any reasons why this might be a bad idea?

First Post and a perhaps rather stupid question regarding MVHR specifications. I've done the calcs for our 150m2 bungalow and get to a requirement of 190m3/h. So when specifying a MVHR unit do I need it to be 190m3/h as that's the total flow through the system on maximum or do I need 380m3/h as the sum of supply and exhaust flows. (I guess I'm just a bit suspicious of how manufacturers might choose to describe their units.) My feeling is that it should be 190m3/h + an allowance for duct loses (I'll probably end up with 70mm semi rigid ducting) so something in the 250-300m3/h range should be good, but don't want to fall into a newbie pooh trap by either under or over specing the unit.