What VMC?

[davido]

I have only just discovered what a VMC is by looking back on some old threads here. I'd been wondering what those big things were in the brico shops .. so now i know. Anyhow, it seems that it's just what I need, but i have a few questions for anyone with the requisite knowledge ..

 

1) what to buy? I looked at leroy Merlin website and they ranged from about 60 euros to  a whopping 950! What's the deal there?

2) If they are constantly on, continually changing the air, doesn't it continually cool the house in winter and warm it in the hot summer months?

3) When you buy one do they come with everything you might need, are are they really just starter packs?

 

hope someone knows more than I do - not hard really

 

davido

[Albert the InfoGipsy]

I'm not familiar with French kit, but essentially there are two types of VMC. One just acts like a glorified extractor fan, sucking air out of the house through ducts from different rooms.

The other sort has a heat exchanger that warms the incoming air with heat from the outgoing. This saves about 3 quarters of the heat that you would lose compared to the first type, if evrything is installed properly.

Neither of them make much sense if you've got a draughty house.

[Gyn_Paul]

There are also versions with humidity detectors which run to vent a steamy bathroom or kitchen and then switch off (or down to the lower speed setting) when the humidity level drops.

I've never seen the point, really, with a house permanently occupied. However in a holiday home, it would keep it aired, certainly.

p