Recommendations for a quiet 10" square heat vent

[heckheck]

Help I can't sleep!

We just had an attic forced air gas heating system installed as part of an addition. The heat system is FAR from quiet. The heating contractor has already been back once and says he doesn't think he can make it much quieter.

I have found by removing a vent cover that the problem is almost 100% due to the air noise created as the air flows through the supply and return vent covers. No covers, no noise, period. Right now he has the supply covers as concentric square louvered vents, with a damper behind the concentric squares. The damper is fully open. For the returns, he has grills with 1/4" slant fins. These whistle like crazy and HAVE TO GO.

I've asked him to slow down the heating fan (it has 4 speeds), but I don't know which speed he has it on now. Obviously too low, and we'll lose efficiency.

We're only heating one master bedroom (plus bathroom and walk in closet) with this system, so I'm considering removing the damper portion of the vents, as I don't think I need it.

Does anybody have a product recommendation for a quiet vent. The vents are on 10" mount boxes fed by 8" flexi tube (I think).

Thanks,

-Jim Heck

[mike_0_007]

had same problem. the original floor registers in my living room had adjustable louvers on them, and were noisy. i took the louvers off (with force) and put the grill back, much quieter.

i often wish i had installed cheaper forced hot water system. The noise of my forced air system is very annoying. But, with it we have central air, so we get noise all summer too!

[m Ransley]

Set the fan too low and you will overheat the coil-to high a temp rise, shortening its life, was it hung from the ceiling.

[heckheck]

Yes it is hung from the roof rafters. I'm fairly certain the noise I'm hearing is noise created right at the vent from air flowing through. I removed one of the ones with slant fins, and it went from locally noisy (a whooshy whistle) to virtually silent in that area.

The room is about 500 sq ft. It has 2 8inch flexible supply lines terminating in 10" boxes, and 2 8inch flexible return lines also from

10" boxes. There is a lot of air being sucked through (though I don't think the fan is at max, perhaps medium). Is that sufficient ducting for a room that size?

-Jim

[m Ransley]

If a supply is near the furnace more air and furnace noise will come out that supply, if it is reduced when removing the grill and full flow is not needed maybe a closeable line damper at the furnace might help by reducing flow a bit. Temp rise must be measured on any install at just above the coil and a return at the furnace, I lowered my fan and found out I was wrong as temp rise exceded the specs in the manual, to high is bad for the coil, if its on its normal low and is to high it indicates a sizing issue of ducts not alowing enough airflow. If its loud now how is it with the AC on, AC has max fan speed. Maybe your installer did not size everything right, Hire a second opinion.

[m Ransley]

Try calling the manufacturer first, they might send someone out. Alot of instals are by hacks.

[Stretch]

Try installing a grille with 1/2 inch spacing between fins, those will be quieter. Better yet get aluminum commercial grilles with 2/3 inch between fins. They are much quieter, but they cost more. Your contractor should be able to get them, but he is likey to cahrge extra, especially if you beat him down on the price. Getting low bid usually bites you on the a--.

Stretch

[Goedjn]

Assuming that the noise you're objecting to is generated at the grill, and not deeper in the system: Swap the 10" box for one that's twice as big. Since the

8" supply tube limits the amount of air you're getting, doubling the size of the outlet will mean you get the same amount of air at half the speed.