trader_4 wrote:
On Sunday, January 11, 2015 at 2:23:38 PM UTC-5, trader_4 wrote:
On Sunday, January 11, 2015 at 1:56:10 PM UTC-5, mcp6453 wrote:
This YouTube video offers an interesting discussion regarding returns on HVAC units in basements. The comments to the
video are worth reading. Which side is right? Should the guy have added a return?

https://www.youtube.com/watch?v=SIwt3kTbCqE


IDK, it raises some good points. Certainly having a return in the basement
is going to help heat the basement with better/proper air flow. IDK where
his claim that the register is going to pull 5% of the air came from. Being
so close to the blower, I would expect it could pull a lot more air than
the same size return located upstairs far away from the furnace.

The issue that you should not have a return essentially at the furnace is
a more interesting one. I see people saying it's a code violation. Maybe,
but I'm not so sure how different that is from say a furnace in an upstairs
utility closet. In that case, you have to have ventilation, eg vents in
the door to let air in for combustion. And you can have returns not far
away, say in the hallway outside the utility room. With vents letting air
flow through the utility closet door, or the utility door open, that seems pretty close to what you have here. That's code compliant, AFAIK, done
frequently, etc. Also, if it's a direct
vent furnace with air supply from outside, as is common today, then I'd
say it's mostly a moot point.


Here's the mechanical code. Check out page 99:

https://law.resource.org/pub/us/code...c.imc.2009.pdf

My interpretation of what's there is that what the youtube guy did
is OK. I only see two things that would possibly apply. First,
it says you can't put a return in a closet, toilet, garage, mechanical
room, furnace room..... If you look at the definitions, furnace room
is defined as a room used primarily for a furnace. Clearly a whole
basement of a house doesn't fit that.

The other thing that could apply would be the 10ft rule, that a return
can't be closer than 10ft to a gas appliance. But it says that only
applies if the return is the only return, so that's out.

So, I think what he did is OK.

Hi,
Simple law of physics.