Supply Cover Question

[Jopopsy]

Hey Gang,

I just tried something over here and I think I may have stumbled on a good idea. Like many who post here, I have a 1 zone system and I futz with things to get more air upstairs as it gets warm in the summer (stat is downstairs). Downstairs I have gobs of air flow.

Today, I pulled off one of the supply covers upstairs and noticed the air flow increased dramatically. This got me to thinking - how do I get this flow going w/ the cover back on?

Since my system has dampers installed in the ductwork, I decided to pull the COVER dampers off. You know, those flaps that open and close w/ the little lever on each cover plate? My thought was every little bit of resistance on these covers seems to put a dent in the flow. I replaced the cover and I did notice better air flow going through the grate. So I then went and pulled the flaps off all the registers on my top floor. Better air flow all around, and my downstairs is still blowing strong. I guess perhaps I'm not leaking air out of the trunks now due to less resistance overall?

Any how, I thought I'd share my experiment in order to get some feedback from everybody. Maybe this can help somebody else. If there is a good reason to NOT do this, pls. let me know. I can put the covers back together.

Jopopsy

[MB1211]

The covers have a rated cfm that can pass through them and changing the cover would make sense that they may pass more cfm. They are really there to balance the flow from the cover. If removing the damper from the cover lets more air through and solves the problem I wouldn't see where it would be a bad thing.

[beenthere]

Hope you saved the louver, so you can put it back in when you switch to heat.
Most second floors tend to heat fine, just not cool as well.

[MB1211]

Hope you saved the louver, so you can put it back in when you switch to heat.
Most second floors tend to heat fine, just not cool as well.

Good point. My mind is either in heating or cooling. I can never seem to remember the other or what may happen in the other mode.

[hangfirew8]

In general, anything that lowers air resistance while still delivering air in the right places is a good thing.

Proper diffusion is all you have to look out for, that is, does the register still throw the air all over the room or is it going in a straight line from the supply to the return and leaving the opposite corner of the room unconditioned.

-HF

[Airmechanical]

now go close off the dampers a "little" down stairs for even MORE airflow up stairs!



.

[air2spare]

that is a great idea, I can't believe SMACNA and ASHRAE never taught us that trick

[Jopopsy]

Hope you saved the louver, so you can put it back in when you switch to heat.
Most second floors tend to heat fine, just not cool as well.

Got that part figured out. I only have 3 vents shut down in the entire house; two of them happen to be in the room where the t-stat is. I'm cooling appropriatly w/ no conditioned air being thrown into the room where the t-stat is. When it gets cold out, I have up to 2 ducts to open up in there.