Fresh Air Return - InspectionNews

K Robertson · #1 (**permalink**) 05-17-2007, 11:14 AM

Are there any rules that prevent a fresh air return from being this close to the condensing unit? I can't find anything, but it just doesn't seem right. And what exactly does this little box that sits by on the fresh air return duct do? First time I've come across one of these. Anyone have any info on this that I can read up on?

Brian E Kelly · #2 (**permalink**) 05-17-2007, 12:25 PM

Not sure of the clearances, but the device you are pointing to is a mechanical damper that opens on command for fresh air.

K Robertson · #3 (**permalink**) 05-17-2007, 02:25 PM

Thanks Brian, but what gives it the command?

Phillip Stojanik · #4 (**permalink**) 05-17-2007, 02:50 PM

Typically the thermostat will have built in controls that monitor the amount of fresh air being brought into the airstream. There may however be a separate controller that looks a bit like a thermostat and often installed in the attic. This type of controller is little more than a timer that opens the intake damper for some programmed number of minutes during a fan cycle.

As far as the intake location goes, there is no specific prohibition about having it that close to the condenser unit discharge but if the system is pulling in hot air discharged from the unit then that heat is being re-introduced into the living space. From an efficiency standpoint that is a poor location from which to draw fresh air.

K Robertson · #5 (**permalink**) 05-17-2007, 07:57 PM

Thanks Philip, I'm just going to say exactly that on the report.

"there is no specific prohibition about having it that close to the condenser unit discharge but if the system is pulling in hot air discharged from the unit then that heat is being re-introduced into the living space. From an efficiency standpoint that is a poor location from which to draw fresh air."

Hope you don't mind my plagiarizing. Thanks.

Thom Walker · #6 (**permalink**) 05-17-2007, 09:12 PM

K,

"there is no specific prohibition about having it that close to the condenser unit discharge but if the system is pulling in hot air discharged from the unit then that heat is being re-introduced into the living space. From an efficiency standpoint that is a poor location from which to draw fresh air." (Phillip said so)

No plagerism.