Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-29-2014, 04:22 PM   #1
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Share |
Default

Improving air flow question (PIC)


Hey guys,

I have a bedroom on my second floor which has extremely poor air flow from the ducts. I can barely feel any air coming out of the register when compared to other rooms in my home.

Here is a pic of the ducts in the basement:



One of those ducts is supplying a bathroom and one is pushing air to the room which has less air flow. I am assuming the smaller diameter is going to that room.

What concerns me is the way it curves down and then up again, I am assuming it will only restrict the air flow and make it worse.

Do you have any suggestions regarding what I should do?

Should I run a bigger diameter duct to that location from my main line? Not sure if that's the proper name for it, I mean the rectangular duct where all the take offs are connected.

It's also not sealed with metal tape or mastic, so that can't be good either.

Any suggestions would be appreciated.

Thanks.


Last edited by VitoB; 01-29-2014 at 04:25 PM.
VitoB is offline   Reply With Quote
Old 01-29-2014, 04:27 PM   #2
Member
 
Join Date: Oct 2011
Location: pa
Posts: 4,293
Default

Improving air flow question (PIC)


1 st make sure the damper at the main trunk is open ...you are correct going down and back up will restrict air flow...maybe take a picture from another angle see if we can't change those runs to a different bay to get rid of those 90s....ben sr

ben's plumbing is offline   Reply With Quote
Old 01-29-2014, 04:48 PM   #3
Member
 
Join Date: Nov 2011
Location: Hartfield VA
Posts: 26,247
Default

Improving air flow question (PIC)


No insulation under the floors.
Uninsulated ducts.
No foil tape or mastic.
No foam on the rim joist.
Hmm bet that basements nice and warm.
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
joecaption is offline   Reply With Quote
Old 01-30-2014, 05:34 AM   #4
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,800
Default

Improving air flow question (PIC)


A pic of the trunk line where they are attached might help us.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is offline   Reply With Quote
Old 01-30-2014, 08:54 AM   #5
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Default

Improving air flow question (PIC)


Here are some additional pics I took this morning. Sorry for the quality. Here is where they connect to the main trunk line:



The thinner square metal duct on the right side is actually the exhaust from my stove in the kitchen, it exhausts from the basement in the floor instead of overhead.

I will need to move it around somehow if I need to modify the ducts that's for sure.

Here is another pic I took further away:

VitoB is offline   Reply With Quote
Old 01-30-2014, 08:59 AM   #6
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Default

Improving air flow question (PIC)


Additional pic of the area, showing another duct running way too close to the rim joists on the exterior wall. I want to change that as well. I added some spray foam but obviously I wasn't able to get good coverage with the duct in the way.

VitoB is offline   Reply With Quote
Old 01-30-2014, 03:50 PM   #7
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,800
Default

Improving air flow question (PIC)


Can the smaller pipe be moved up one bay and ran with the other dust. if so, then you could move the poor air flow one into the bay that the small one was in.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is offline   Reply With Quote
Old 01-30-2014, 06:04 PM   #8
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Default

Improving air flow question (PIC)


I am willing to do whatever it takes. I can cut into the main trunk line if necessary. The duct running along the outside wall also needs to be moved since I cannot properly insulate the rim joist.
VitoB is offline   Reply With Quote
Old 01-31-2014, 12:39 PM   #9
Member
 
Join Date: Apr 2013
Location: Chantry Ontario
Posts: 76
Default

Improving air flow question (PIC)


Check to make sure that the cold room has an adequate return to the furnace, or it will be tough to get any heat to it no matter what else you do. If it doesn't have it's own return, to properly heat it you will need to make sure the door is always slightly open, or it has quite a large crack under the door.

Simple test for this: Get a helper to slooowly crack open the door to that room while you are inside it with your hand on the hot air register. If the hot air coming in picks up speed when the door opens then the room doesn't have proper return. In that case leaving the door open an inch all the time if possible will make a huge difference.

Last edited by ChantryOntario; 01-31-2014 at 12:45 PM.
ChantryOntario is offline   Reply With Quote
Old 01-31-2014, 12:50 PM   #10
Member
 
Join Date: Jan 2014
Posts: 455
Default

Improving air flow question (PIC)


Can you close off or restrict some of the other vents in the house to force more of the air to the colder room? This may just be an issue of balancing. Also, one of those branches in your picture shows it's loose from the trunk near the top, I can see dust buildup on the outside of the trunk. Those lose connections need to be sealed up.
IslandGuy is offline   Reply With Quote
Old 02-01-2014, 03:41 PM   #11
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Default

Improving air flow question (PIC)


Quote:
Originally Posted by ChantryOntario View Post
Check to make sure that the cold room has an adequate return to the furnace, or it will be tough to get any heat to it no matter what else you do. If it doesn't have it's own return, to properly heat it you will need to make sure the door is always slightly open, or it has quite a large crack under the door.

Simple test for this: Get a helper to slooowly crack open the door to that room while you are inside it with your hand on the hot air register. If the hot air coming in picks up speed when the door opens then the room doesn't have proper return. In that case leaving the door open an inch all the time if possible will make a huge difference.
The return does seem a bit weird in this room now that you mention it, the opening isn't that large. To be honest I am not even sure if it actually connects to the air return cavities in the wall. With the grille removed, I can see the drywall from my kitchen ceiling. I will try to see where it leads to.

Quote:
Originally Posted by IslandGuy View Post
Can you close off or restrict some of the other vents in the house to force more of the air to the colder room? This may just be an issue of balancing. Also, one of those branches in your picture shows it's loose from the trunk near the top, I can see dust buildup on the outside of the trunk. Those lose connections need to be sealed up.
I would actually like to redo the ducts from the main trunk line, especially that 4 inch one. I am planning on adding a 6 inch duct from the main trunk line and then installing a reducer going from 6 inch to 4 inch so that I can connect to the current line going up to the colder room.

Not sure if that's a good idea or not, I haven't really done any HVAC work before.
VitoB is offline   Reply With Quote
Old 02-01-2014, 04:18 PM   #12
Member
 
Join Date: Dec 2011
Location: zentral Iowa
Posts: 1,179
Default

Improving air flow question (PIC)


two-stories are notorious for poor air flow.

You want to have 8" supply lines and plenty of return.

What most people do is just get used to the cold. Why do you want it to be warm in the bedroom anyway?

Be thankful that you aren't in an area where you need to get cold air up there in the summer.
cleveman is offline   Reply With Quote
Old 02-01-2014, 04:26 PM   #13
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Default

Improving air flow question (PIC)


Quote:
Originally Posted by cleveman View Post
two-stories are notorious for poor air flow.

You want to have 8" supply lines and plenty of return.

What most people do is just get used to the cold. Why do you want it to be warm in the bedroom anyway?

Be thankful that you aren't in an area where you need to get cold air up there in the summer.
I live in Canada, we're talking extreme cold here, it can go down to -35 degrees celcius in the winter.

I understand the bedroom doesn't need to be crazy hot, but right now I find the room is almost unusable. We plan on starting a family soon, I don't see myself making this a baby room with how cold it is in there.
VitoB is offline   Reply With Quote
Old 02-01-2014, 04:36 PM   #14
DIYer
 
Join Date: Nov 2012
Location: Montreal, Canada
Posts: 80
Default

Improving air flow question (PIC)


By the way is there any point in wrapping the rigid ducts with insulation in the basement? Or would it be pointless since they are on the warm side?
VitoB is offline   Reply With Quote
Old 02-02-2014, 11:38 AM   #15
Member
 
Join Date: Dec 2011
Location: zentral Iowa
Posts: 1,179
Default

Improving air flow question (PIC)


I have my thermostat set at 68 F and it is normally 64 in the upstairs, so I feel you pain. I don't mind it too much in the winter, but in the summer I could use it cooler.

If you run a humidifier and get your humidity around 45% when the outside temperature permits, this will make it feel warmer.

It isn't unhealthy to sleep in cooler temperatures and there are a lot of nice and warm jump suits for babies.

I can only repeat that you should run 8" runs to the upstairs. If you replace the existing 6" with 8" at this point, you'll be trying to force it through rectangular duct in the walls at some point, but it may help.

As someone else already suggested, you can damper down your other lines and see it that helps. You can also partially close registers if you don't have dampers.

Another thing is to run your furnace fan continuously.

Again, it is a common problem. I'm told that the only good way to deal with it is to put a furnace on both floors. And again, just wait until you try to push cool air up there in the summer, should you ever have the need for a/c.

cleveman is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hot Water Flow kcirtap23 Plumbing 1 02-10-2012 04:11 PM
Generator connection Question - Final Plan Apollo67 Electrical 24 01-30-2012 07:44 PM
Low flow beer_geek Plumbing 9 10-24-2008 06:32 AM
Basement Renovation Question KUIPORNG Remodeling 234 08-26-2008 08:19 AM
hrv question indep HVAC 3 07-17-2008 10:39 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.