HRV flue combination
I notice on the web there are several references to HRV+flue combinations. I’ve not seen a discussion of that here though.
In concept it seems like it would be very efficient since the very cold incoming air could accept heat more readily than the indoor ambient air of a normal HRV.
A risk seems like possible increase in creosote condensation. I’m wondering though if it might actually be able to detect and slow a flue fire?
I suppose reduction in draft might be possible if it cools the flue too much, but if it’s really a balanced system, that hypothetically should be resolved and it could even be programmed to increase draft when needed.
So what are people’s thoughts and experiences?
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Replies
Jason,
I have never seen the device you describe. What is the brand name? Do you have a Web link?
It makes no sense to try to cool a flue used to vent a wood stove. You're right that you don't want to encourage the formation of creosote.
https://www.youtube.com/watch?v=_wse-ckYoe8
Jason is this what you are referring to? If so this might be slightly better than "ventilating you clothes dryer inside the building envelope" on the list of terrible ideas to save energy. You are correct that you are going to increase the risk of creosote generation. Also, if the ductwork is not properly sealed you run the risk of distributing contaminants such as smoke and carbon monoxide throughout the house.
Trevor,
The YouTube video you linked to is not a commercial product -- just an idea. Needless to say, it's not a very good idea. Just to emphasize the point that the developer of this idea isn't particularly interested in green construction, the sketch includes a snowmelt system using hot water pipes outdoors.