Comments on: The Third Worst Place to Put a Duct

By: David

David — Fri, 17 Jul 2020 22:22:38 +0000

I don't fell bad now because
I don't fell bad now because my home was built in 1974 it's a rambler/rancher house and the 3 bedrooms upstairs has the return vents at floor level on one side of the rooms and the supply vents on the opposite side of the rooms which is dumb because cool air conditioned air is heavier so I just don't understand why the HVAC guys who did the duct work when the house was built would put the return vents at floor level when the return vents need to be at the top of the rooms to suck out the warm air the raises to the top of the rooms, the only return that's in the right place is the one in the hallway that return is in the ceiling

By: Tmiller

Tmiller — Fri, 10 Jul 2020 05:05:02 +0000

I noticed my electrical
I noticed my electrical outlet was a little warped. So I took the plate off and noticed moisture! the outlet is on an outside wall and is close to the ac unit. Our vents are located in the floor and very close to the electrical outlet. Here in Alabama it is very humid. Could the fact the vents are so close to the outlets and on an outside wall cause condensation?

By: Robin W Boyd

Robin W Boyd — Wed, 24 Jun 2020 21:31:19 +0000

In reply to Joan Pappas. If this issue is occurring
If this issue is occurring only in one room, there is something about that room that is at fault; not the HVAC system. If you have more dust in that room, and the humidity level is a bit higher; and...the surface temperature of the dusty areas is cooler, then the air stream from the vent could very well be causing the existing dust to stick to the cooler surfaces by condensing the moisture in the air on those surfaces. I have investigated many "ghosting" situations where cooler walls collect dust in stripes coinciding with wall and ceiling studs. Also, dust accumulation where carpeting meets walls or is penetrated by floor vents is also caused by these factors.

By: Joan Pappas

Joan Pappas — Wed, 24 Jun 2020 20:49:53 +0000

WE HAVE HAD SEVERAL HVAC
WE HAVE HAD SEVERAL HVAC "EXPERTS" LOOK AT A STRANGE PROBLEM WITH EXCESS DUST. ONE BEDROOM GETS AN EXTRAORDINARY BUILDUP. LOOKING OFF SIDE OF WALLS WITH FLASHLITE, THERE IS A GENEROUS COATING OF DUST WHICH IS ESPECIALLY BAD IN THE PATH OF THE CEILING OUTPUT VENT. THE WHOLE ROOM GETS MUCH MORE THAN OTHER ROOMS IN HOME. WE HAVE GAS HEAT AND HEATPUMP FOR AC. ORIGINAL SYSTEM WAS HEATPUMP W/PROPANE BACKUP UNTIL NAT.GAS CAME INTO AREA. HOME IS 14 YRS OLD & WE ARE ORIGINAL OWNERS (HAD HOME BUILT). THE INTAKE VENTS ARE NOT SEALED WITH MASTIC AND THE OUTPUT VENTS ARE NOT EITHER. THERE WAS NO CODE TO DO SO IN NC WHEN WE BUILT. DON'T KNOW IF THERE IS NOW. ANY IDEA ABOUT WHAT IS CAUSING THIS? THANK YOU. JOAN

By: Don Cobb

Don Cobb — Thu, 07 May 2020 19:50:27 +0000

In reply to abailes. You are exactly right putting
You are exactly right putting one on the exterior walls not the ideal thing to do that’s why it is insulated behind it with your house insulation and you put all your supply actually Windows And Doors for your heat loss and your heat gain is so please quit misleading people they have to be with the windows and doors are

By: paul r

paul r — Sat, 22 Feb 2020 13:31:49 +0000

I'm having central air
I'm having central air,including ductwork, installed in a 100 yr old home in NJ. One of the contractors I'm considering uses hardpipe that is insulated on the inside using a non-fibrous, flexible, polyimide foam insulation developed specifically for use as a thermal/ acoustic liner in ductwork. My understanding is that it doesn't have the potential air quality issues associated with fiber glass internal liners. It looks like this foam insulation has been approved for use by the NY Department of buildings. I have one particular room where the best way to get a supply vent into it would be to locate the supply duct in an exterior wall. Since the duct would be insulated on the insider I'm wondering if this would address the concern about condensation. I'd be interested in your thoughts on using this type of duct liner in general and specifically in an external wall for this one room.

By: MattF

MattF — Thu, 02 Jan 2020 20:51:46 +0000

Here is one for the “worst
Here is one for the “worst place to put a duct”…outside:
https://www.greenbuildingadvisor.com/question/external-ducting-sealing#comment-169596?utm_medium=email&utm_source=notification&utm_campaign=comment_notification&utm_content=view

Also a winner for most ridiculous duct sealing job ever.

By: Robin Boyd

Robin Boyd — Tue, 10 Sep 2019 00:39:14 +0000

There are several issues that
There are several issues that could be occurring with a downflow system. Yes, increasing the return air volume will decrease the static pressure that is most likely not allowing the condensate trap, if there is one and it is deep enough, to work properly. Other issues that occur with downflow systems have to do with condensate forming on the bottom of the drain pan, condensate being blown out of the drain pan and condensate being blown off of tubing on the coil. In the downflow position, the cooled air is causing the drain pan to cool below dew point so that any moisture in the air stream beneath the coil is going to condensate. The bottom of the drain pan and exposed tubing on the coil need to be insulated to prevent condensate issues. Since the airflow is hitting the inside of the coil drain pan, downflow systems often have condensate in the drain pan blow out of the drain pan due to the air becoming turbulent in the drain pan. A 1-1/2 inch piece of metal, the length of the coil, placed where ever the coil sets in the drain pan will prevent this from occurring.

By: Hoang

Hoang — Mon, 09 Sep 2019 22:04:29 +0000

Hi, I currently have an issue
Hi, I currently have an issue with my AC evap coil leaking water of over the ledge of the drain pan. it is an down flow with N coil. Last month a HVAC tech came and retrofit my ducting. He removed the 12 inch return (the return duct was only a few feet from the blower and it is the only return in the home). it was very noisy because it was next to our living room. My intention was for them to add a 10 inch return duct to down stair to minimize the noise but instead they took out the 12 in and just add the 10 inch down only to the joist space down stair. I know have a water leaking issue probably due to high velocity causing turbulence in the coil space and probably lack of air. I had another tech come and now they are telling me to leave the 10 inch duct there and add two 6 inch duct where the 12 inch was and add it to the return. Just do to space restriction and the design of the house I don't think they can do any thing else except ripping all the drywall and re do all ducting which is major work. Do you think the new set up will minimize the air return noise? and eliminate the water leaking issue. Brand new evap coil. Thanks

By: Albany Landlord

Albany Landlord — Mon, 19 Aug 2019 05:29:44 +0000

In reply to Andy Kosick . I was at a friends house
I was at a friends house after reading this and they have a toe kick register.... centered on the kitchen sink. You know the one spot in the house you stand at most often? Do we have a winner?