Backdraft Dampers at Each Ceiling Register
kramttocs
| Posted in General Questions on
For an attic hvac system (heatpump), is there a downside to adding backdraft dampers to each ceiling register? Besides purchase cost. My ductwork is all removed right now for a reinsulation/airsealing project.
All registers have a 90 or 45 coming off the boot so they’d be installed upstream of that either in the horizontal or angled position so the flap falls into the closed position by default.
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Replies
This would have been great to answer yesterday! All those dampers going BUMP in the night on Halloween. Next you’d need someone pulling chains across the attic floor :-)
In all seriousness, the noise of them falling shut at the end of each run cycle would probably be very annoying. I don’t see that you’d be accomplishing all that much either, assuming a properly sealed HVAC system.
Bill
Hey Bill. Hmm didn't think about noise but yes, seeing as the kids sleep upstairs, making them rattle at the right time could be entertaining...
The reason I thought about this was that I have the vent boots all plugged with towels from above right now since we've had a few <30F days this week and I am not done insulating. So the downstairs heatpump was the only source of heat those days and while I am sure a lot had to do with the ground still being warm, it only ran a couple of times a day which is very unusual for this 1970's cape cod. Got to thinking that besides all the air sealing I've done, maybe a lot is being lost up the vents. The ductwork was not sealed well nor insulated well, which I will be redoing but still thought it might be worth it.
I've had good luck with AC Infinity stuff and I see they have 6" dampers with rubber o-rings that might eliminate the noise?
Of course this doesn't do much for the large return right at the top of the stairs. Perhaps, properly sealing the unit and then burying it all in insulation is the best all around option.
MY only experience with backdraft damper had them installed in the swamp cooler registers that were separate system from the AC. Whenever a strong wind would change direction every register in the house would all make a clapping noise almost in unison. Very annoying.