# return air for gas furnace / a/c

| Posted in General Questions on

A different thought? (Trying to understand return air). Say a furnace is installed in the hallway and there are no ra ducts. The ra grill is on the front of the furnace. and there is no closet door in front of the furnace. Say the ra grilles on the front of the furnace are two, 16×20’s but, the louvered area is actually 14×17 = 238 x 2 = 476 sq ” (of size) and then that would be reduced say by 75% because of the louveres = 357sq”, and then reduced again say by 75% when adding filters leaves only 267sq ” for return air. Would this 267 sq ” be the maximum amount for ra (or of return air ?) that this furnace would have for this type of system? Providing there is no air blockage in the hallwall.

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### Replies

1. Riversong | | #1

No one else is responding, so I'll take a shot at it.

Return air is what you get your deposit refunded for, and what you have to pay a fine for if not returned on time.

2. GBA Editor
| | #2

James,
By my count, you've posted this question three times. In addition to this question posted on Sept. 21, you posted it twice before: