ERV for radon remediation in basement – dedicated venting design
Hi,
I plan to install an ERV in my basement with a dedicated venting system. I have two HVAC systems in the basement with inlet air registers 1 foot above the basement floor.
My questions:
1. Given that radon has specific gravity seven times that of air, should I relocate the HVAC inlet registers near the ceiling?
2. Should ERV return (stale air) registers be placed near the floor?
3. Should ERV fresh air registers be placed in or near the ceiling?
Many thanks in advance,
Tony
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Replies
How much the radon settles near the ground depends a lot on how much mixing there is in the air. My gut feel that putting the return near the ceiling is a good idea especially if not a lot of work.
The ERV stale air pickup should definitely be near ground level.
The best is to duct the supply to the return of your furnace. Just make sure there isn't too much pressure drop there when the furnace runs as it can unbalance the ERV. If the return register is large and the ERV is connected close to the register, it should not be an issue. This way the furnace can tamper the fresh air supply and distribute it through the house. You can T the ERV fresh air supply to feed both furnace returns.