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bigkev8624
Portable A/C Venting?

The 3rd floor of our home is an attic space that's been converted to a master suite. It has central air, but it just doesn't get cool enough up there. I've purchased a portable a/c unit that does a great job giving us the extra cooling. There are windows available for the venting, but the ideal spot for the unit doesn't have a window nearby. It does have access to a return air vent though. Could I pop off the cover and stick the 3' a/c venting hose down that return air duct? Not sure if this would be a problem or okay.

Any advice would be appreciated. Thanks!
-Kevin

Sten
Re: Portable A/C Venting?

Shouldn't hurt anything, just make sure you put it in the return and not the supply.

NW HVAC Tech
Re: Portable A/C Venting?
bigkev8624 wrote:

The 3rd floor of our home is an attic space that's been converted to a master suite. It has central air, but it just doesn't get cool enough up there. I've purchased a portable a/c unit that does a great job giving us the extra cooling. There are windows available for the venting, but the ideal spot for the unit doesn't have a window nearby. It does have access to a return air vent though. Could I pop off the cover and stick the 3' a/c venting hose down that return air duct? Not sure if this would be a problem or okay.

Any advice would be appreciated. Thanks!
-Kevin

Putting the vent hose into the return is not optimal as the heat generated by the compressor work and the heat removed from the master would be dumped onto the central system so you'll pay more than twice to cool your room, better to look at venting to the outdoors. Also of note is that with many of these units if they only have one "hose" or duct the use indoor air for the heat rejection part of the system which is also wasteful. The units with two ducts vented to the outside one for intake and one for exhaust are much better. If you do decide to dump into your return you will want to set the fan selector switch to the on position.

bigkev8624
Re: Portable A/C Venting?

So we've got one Yes and one No....can someone be the tie-breaker?

A. Spruce
Re: Portable A/C Venting?

I would vote no for the same reasons posted, why do you want to make you main AC unit work harder when you can vent to the exterior. While it may be optimal to place the unit away from the window, I'd rather sacrifice a little in this one room than drive up operating costs for the entire house.

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