Where to locate HRV with deep basement?
Due to excessive window condensation in the winter, I want to install an HRV. The problem is that our house is fairly deep in the ground so going through the rim joist with the vents leaves very little clearance for snow, leaves, and critters.
I will be doing the simple install tying into existing ductwork; I have enough electrical experience to come up with a furnace fan interlock.
I have thought about installing it at the top of one closet we have that is on an exterior wall, but space will be tight for installation and servicing. Could I just pull air from the closest (perhaps installing a louver in the door) as this would mean only one duct out of the closet?
Thanks in advance!
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Paul,
I'm not sure I understand your question. I'll try to rephrase it. Tell me if I have this right: "I plan to install an HRV in a closet. I will hook up the two usual ducts that connect to the outdoors (the fresh air duct from the exterior to the HRV, and the exhaust duct from the HRV to the exterior). I will then hook up the duct that supplies fresh air to the house by installing a duct that connects the HRV to the furnace ductwork. But I don't want to pull stale air from the bathrooms, as most people do. Instead, I want to pull air stale air from the closet."
Is that right?
Hi Martin,
Yes, that's what I'm proposing. Retrofitting ducts to the bathrooms will be difficult and result in long runs. The closet is just off the kitchen at the opposite end from the bedrooms (bungalow) so this seems like a reasonable area to pull stale air from.
Paul,
As you may know, I'm not a fan of HRVs that try to use forced-air heating ducts to distribute ventilation air. It's far preferable to use dedicated ventilation ductwork. For more information on some of the challenges associated with these systems, see Ducting HRVs and ERVs.
HRVs have the capacity to pull stale air out of smelly rooms and to distribute fresh air to rooms where people spend the most hours of the day, and to perform these tasks without using much electricity. Your system will miss out on many of the benefits of HRVs, by not pulling stale air from the rooms where you want to be getting that air, and by using more electricity than necessary (assuming that the furnace fan is used to distribute ventilation air).
I have previously read that article and it all makes sense. I guess it's a trade-off of an ideal system versus ease of installation!
Is it possible to put the HRV in the basement and run the intake/exhaust ducts throught the closet?
Yes, the ducts could be run up through a closet, but it becomes difficult with two bulky insulated ducts and duct length starts to become excessive. Our dryer exhaust and furnace supply and vent pipes run up into the back of our kitchen cupboards and then out through the wall. We can't do this with the HRV ducts though as it would be too close to the other vents and possibly draw in their exhaust.
My original idea won't work anyways as there is not enough space at the top of the closet to fit an HRV. Back to the drawing board!