Soffit / eave exhaust and intake vent cap
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Any recommended alternatives to the Panasonic EZ Vent dampered soffit vents that are relatively airtight?
For various reasons, I need to vent through the soffit and the EZ Vents wont fit, so I need alternative soffits termination for the bath, ERV and kitchen hood exhaust. Seems like it should be dampered.
I will also need soffit terminations for the ERV and kitchen hood intakes (they are far from the exhaust). Not sure if these are supposed to be dampered – the dampers would need to go the other way but it seems like a good idea.
Both Lambro and Imperial make a soffit vent with a damper, but both seem rather flimsy – the damper does not fit tight. And yes, the terminations need to be in the soffit and can’t be elsewhere.
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Replies
CL,
You probably want to look at an inline damper. This approach will give you more options.
Thanks. I think the Panasonic bath fans and ERV's have inline dampers, but I'm not sure how effective they are. Even with an inline damper, I'd want it to be close to the exterior because a) at this point the soffit is the only part I can sort of get to, and b) I'd like to keep insects out.
Any recommendation on an inline damper the works based on air pressure, yet does not restrict the exhaust or intake?
CL,
These dampers do that: https://www.conservationmart.com/p-504-tamarack-cape-4-in-backdraft-damper-cbd4.aspx
I haven't used them. I think it was Michael Maines who recommended them here?
Malcom, thank you for the link. Those are really interesting.
So that brings up the question of which type of damper is better for a Panasonic Bath fan or Panasonic ERV ?
1. Damper that is well sealed such as butterfly damper with neoprene, that has good reverse air flow seal, reducing the probability of letting let air backdraft from an ERV supply, or escape under house pressure via the ERV or bath exhaust, thereby keeping the house tighter when the device is not in use, but requiring the fan to work harder (more static pressure) when the device is on?
or
2. Damper with very low static pressure, such as this Tamarack product, that will allow the exhaust fan to run most efficiently when in use, but that might not be as effective at preventing backdraft?
I suspect the response might be different for the bath vs the ERV fan.
The bath fan only runs a few times a day, and if the ducted exhaust path already has low static pressure (no or minimal turns) perhaps the butterfly damper is a better option? If so, which one?
The ERV runs on and off all the time, and the fan has to both pull in air from a ducted supply and push out air via a ducted exhaust thus more total static pressure even if the duct has minimal turns. Perhaps in that case these Tamarack dampers are best, installed the opposite directions, near exterior at both supply and exhaust?