[Flutterby]

Well we have arrived to discover that DP's parents have had this fitted in the last year since we visited, i don't know much about it but they seem very happy with the results, My concern is that they will be paying a lot of money on heating and it will be going straight up through the roof.
Does anybody have this or has looked into this? Any past experiences of it?
I'll do some more research later but i'm trying to not use too much of MIL's limited internet allowance.

[andrewp]

We have one and I'm very impressed. Bear in mind that the main reason for them (IMHO) is to limit condensation. We never have wet windows in our house. It really does work well in removing all that damp air. And as soon as there is a hint of sun shine (which seems to be almost every day) the roof cavity warms up very quickly. Our one has a temp readout for in the house and in the roof. I also have a weather station and so have been tracking the temps quite closely. I often see a temp in the roof 8-10 degrees warmier than the ourside temp. It's been quite comon to feel lovely warm dry air streaming in to the house through all the vents when it's freezing outside.

If you can't tell... YES. We are very happy with ours. You still need a form of heating in the house, but it really does work for us.

[constablechuck]

Were getting an HRV system installed in our house tomorrow. I will give an update in a couple of weeks on how it works.

[James 1077]

Tia Maria has an HRV system in her new house - PM her to find out more if you are interested!

[Nienke]

We've had a dvs system (same principle) installed 2 months ago and I'm very impressed with it. No more condensation on the windows, and heating costs haven't gone up at all. In fact, on sunny days like today it makes the house warmer because it pumps the hot air from the roof into the house.

[JasonS]

we have a synergy smart vent, which is a "true" HRV in the terms of a heat recovery system. it pulls the warm air from your warmest rooms and that warmer air is circulated through the system to help heat the air coming into the system (from the roof space). we have a wood burner in the lounge, so that it the source of most of the heat into the system. anyways, the idea is to decrease the moisture in the air with an exchange of dryer air into the house, and the bad moist air is sent out. so with the air being dryer in the house, it is easier to heat, thus having to use less energy (heat) to warm the air in your house.

the smart vent is great for getting the moisture out of the house, but the heat transfer from our lounge down to the bedrooms is not as impressive as we would have liked. we might install a separate heat transfer kit to do that. another nice thing about the smart vent is that there is a summer option that will switch a damper in the system that will pull air from outside, instead of the attic space, and there will not be any heat exchange at that time as well. so, our house stays pretty comfy during the summer and does not get too hot when we are are not home to open the windows.

so, in the long run it has definitely saved us money. we noticed that our wood consumption with the wood burner decreased significantly after getting it installed.

laurel

[Flutterby]

thankyou this has all been useful information