View Full Version : plenum take off - is it recommended?

01-15-2007, 09:49 AM
Greetings -

Looking for advice with respect to routing duct work.

It is an existing duct system that uses 14x8 rect. metal duct work - simple setup one run for the hot and another for the return.

The location of the furnace is in the basement directly below the family room. The family room tends to be on the cooler side in winter. I would like to place a 6" take off from the plenum to the family room existing register I have seen this done at other locations but wanted to know GENERALLY if this is ok and if it will detract from the effectiveness of the entire system.

Would appreciate any info.

01-15-2007, 04:43 PM
I'ts OK as long as you put a volume damper close to the take off to control the amount of air flow.The propper way would be to increase the size of your duct that supplies this area and take-off the duct to supply this room.This is more expensive and the other is cheaper.Sometimes cheaper is better.tinman101

01-16-2007, 04:53 PM
If I understand what your saying correctly you want to insatll a 6" dia take off on the plenum to supply the family room? By general rule or thumb this is a no-no, but one run is not goiong to afect the system. Like tinman said in stall a damper at the takeoff. As close to start of line as possible. Furnaces relay on satic pressure in the plemuns to build up and burst down the duct run. To many take offs on the plenum, and I've seen some doosies, takes away from this pressure buildup. I've got 2 on my furnace that ive just replaced, and they are going back on my new plenum. Easier to connect there then run pipe from halfway up the house off the main line and back to the furnace.
Cheapier aint better just alot easier. lol

till then...