Anyplace Online to Learn About Ductwork?

Joeski · Post by **Joeski** » Tue. Feb. 12, 2013 6:46 pm

Hi all you coalpail.comer's. I'm trying to learn as much as I can about distributing my warm air from my stoker to all parts of my house. Do you know of any places online where I can read about this. All the Google search's gives me really simple repairs & contractors. This is one keyword I typed in. "online learning of home duct systems"

Thank you very much in advance.

Joeski

Post by **Lightning** » Tue. Feb. 12, 2013 7:00 pm

Hey Rigar!! This guy over here needs your expertise

Member Rigar is good with duct work and air flow questions. Hit him up

McGiever · Post by **McGiever** » Tue. Feb. 12, 2013 7:48 pm

Here's some reading.

Duct Layout @ Google

Rigar · Post by **Rigar** » Tue. Feb. 12, 2013 7:54 pm

Lightning wrote:Hey Rigar!! This guy over here needs your expertise

Member Rigar is good with duct work and air flow questions. Hit him up

...I"ll happily try to answer any questions Joeski

Rigar · Post by **Rigar** » Tue. Feb. 12, 2013 8:08 pm

Off the top of my head...greymetal may offer flow charts for various size ducts online
..
The most important thing in my oppinion if you are "retrofitting" for lack of better word...(as opposed to having a system built specifically for your home)...is to guage each supply duct to each room
as adequate as possible.
If the home is of newer construction...there are some pretty basic " rules of thumb" that should work pretty good for you.
Location of supply vents and return air vents is important...
...but more importantly in your case would be to "design" your set up around the capabilities of your current furnace..
... BTU output and convection blower size (cfm)

Joeski · Post by **Joeski** » Tue. Feb. 12, 2013 8:25 pm

Lightning wrote:Hey Rigar!! This guy over here needs your expertise

Member Rigar is good with duct work and air flow questions. Hit him up

Thanks

Joeski · Post by **Joeski** » Tue. Feb. 12, 2013 8:26 pm

McGiever wrote:Here's some reading.

Duct Layout @ Google

Thanks, I'll be reading a lot from what I have seen so far.

Joeski · Post by **Joeski** » Tue. Feb. 12, 2013 8:28 pm

Rigar wrote:
Lightning wrote:Hey Rigar!! This guy over here needs your expertise

Member Rigar is good with duct work and air flow questions. Hit him up
...I"ll happily try to answer any questions Joeski

Thank you

I want to ask the questions with photo's attached so you can see what I am trying to do. This weekend I'll hopefully find the charger to my digital camera battery so I can take them.

Joeski · Post by **Joeski** » Tue. Feb. 12, 2013 8:35 pm

Rigar wrote:Off the top of my head...greymetal may offer flow charts for various size ducts online
..
The most important thing in my oppinion if you are "retrofitting" for lack of better word...(as opposed to having a system built specifically for your home)...is to guage each supply duct to each room
as adequate as possible.I think the previous owner didn't get that done quite well by whoever did it for them. And the old owners put a 1/3 HP motor in to power the blower when the manual calls for 3/4 HP. I am pretty sure that is why the ducts farthest from the blower gets zero air flow.
If the home is of newer construction...there are some pretty basic " rules of thumb" that should work pretty good for you.

It is a 1992. Is the age in the range for the "rules of thumb"?

Location of supply vents and return air vents is important...
...but more importantly in your case would be to "design" your set up around the capabilities of your current furnace..
... BTU output and convection blower size (cfm)

It has a nozzle for 120,000 or 150,000 btu.

I'll have to check for sure. And I'll look at the cfm too when I check the btu's.

Rigar · Post by **Rigar** » Tue. Feb. 12, 2013 8:49 pm

Is the blower belt drve??

There is no way a 1/3 hp motor could power a belt drive blower designed for a 3/4 hp motor UNLESS they either changed the motor drive pulley or fan drive pulley size.
what is make and model of blower assembly

Rigar · Post by **Rigar** » Tue. Feb. 12, 2013 8:52 pm

What is drive pulley diameter?
What is fan pulley diameter
width of blower
diameter of blower
rpm on motor (im assuming 1755 rpm ?)
Im guessing blower isnt moving the air it could

steamup · Post by **steamup** » Fri. Feb. 15, 2013 8:09 am

air duct sizing infor

http://www.engineeringtoolbox.com/air-ducts-sizin ... _1736.html

When changing fan volumes, keep in mind the fan laws:

http://www.engineeringtoolbox.com/fan-affinity-la ... d_196.html

Note the horsepower is to the power of 3 of volume change.

Joeski · Post by **Joeski** » Mon. Feb. 18, 2013 7:41 pm

Rigar wrote:Is the blower belt drve?? Yes

There is no way a 1/3 hp motor could power a belt drive blower designed for a 3/4 hp motor UNLESS they either changed the motor drive pulley or fan drive pulley size.
what is make and model of blower assembly

Ok then someone must have done that. I will have to dig around to see what is the make and model it is. I won't be able to check for a little while though.

Thanks again

Joeski · Post by **Joeski** » Mon. Feb. 18, 2013 7:42 pm

Rigar wrote:What is drive pulley diameter?
What is fan pulley diameter
width of blower
diameter of blower
rpm on motor (im assuming 1755 rpm ?)
Im guessing blower isnt moving the air it could

I'm going to have to look and find all these #'s or measure them then I'll post them here. Thanks again Rigar.

Joeski · Post by **Joeski** » Mon. Feb. 18, 2013 7:44 pm

steamup wrote:air duct sizing infor

http://www.engineeringtoolbox.com/air-ducts-sizin ... _1736.html

When changing fan volumes, keep in mind the fan laws:

http://www.engineeringtoolbox.com/fan-affinity-la ... d_196.html

Note the horsepower is to the power of 3 of volume change.

Hi steamup. Thank you very much for these. I have to get reading, reading & more reading too.