4 Ducts Going To Chimney, Or 1? - HVAC - DIY Chatroom Home Improvement Forum


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

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

Reply
 
Thread Tools Display Modes
Old 10-10-2012, 12:19 PM   #1
Member
 
Join Date: Apr 2012
Location: Glenside, PA
Posts: 82
Rewards Points: 75
Default

4 ducts going to chimney, or 1?


My friend is having me do some work over at his duplex. He needs to reline his chimney, so we're going to do that with a DIY kit that he's getting online. It comes with everything: 6-inch SS flex liner, tee (for coming into the basement from the liner), insulation kit, rain cap, top plate, & high-temp caulk.

Now, the problem is this - Being a duplex, he has 2 furnaces and 2 water heaters. Right now all four of the vent ducts are going into the chimney separately (see picture):



How should we run all of 4 of these into that tee that comes with the liner kit? Can I just run all 4 into one "junction" so to speak, and then out through the tee, or do I have to run them each separately into the chimney like they are now? The first way would look a lot nicer, and I feel it would be just as effective as the latter way. Thanks!

Advertisement

Chris Sweeney is offline   Reply With Quote
Old 10-10-2012, 01:05 PM   #2
HVAC Tech/Owner
 
Join Date: Nov 2010
Location: VA
Posts: 513
Rewards Points: 350
Default

4 ducts going to chimney, or 1?


How did he determine 6" is the right size?

Draft requirements are very specific and just like ductwork you can't just hookup some pipe and hope it works.

What are the btu inputs of the appliances? How much vertical height, how much horizontal distances??

"Danger Will Robinson"

Advertisement

Technow is offline   Reply With Quote
Old 10-10-2012, 04:37 PM   #3
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,458
Rewards Points: 4,562
Default

4 ducts going to chimney, or 1?


Use wyes to tie each units vent to the liner.

6" liner may or may not be big enough. So ask him how he determined size.
beenthere is online now   Reply With Quote
Old 10-10-2012, 05:57 PM   #4
Member
 
Join Date: Dec 2009
Posts: 637
Rewards Points: 500
Default

4 ducts going to chimney, or 1?


Unless you're a ticketed gas fitter, you should not be doing this work. I'm all for DIY, even when it comes to gas, but this sounds like a rental to me. Home owners can pull permits where I live, but only if it's their own single family home that they live in, they are doing the work themselves, and aren't paying anyone to do the work (ie. you have a right as a home owner to possibly endanger yourself and immediate family, but no one else). The scope of work is beyond what you can or should do.
hvac benny is offline   Reply With Quote
Old 10-10-2012, 06:18 PM   #5
Member
 
Join Date: Mar 2010
Location: PENNSYLVANIA
Posts: 2,258
Rewards Points: 1,044
Default

4 ducts going to chimney, or 1?


Looks like a double Chimney setup, why not run two liners one for each house. He's still saving big $$$$.
__________________
No Warranty Means- If it breaks in half you get to keep both halves.
COLDIRON is offline   Reply With Quote
Old 10-10-2012, 09:07 PM   #6
Member
 
Join Date: Apr 2012
Location: Glenside, PA
Posts: 82
Rewards Points: 75
Default

4 ducts going to chimney, or 1?


Quote:
Originally Posted by Technow View Post
How did he determine 6" is the right size?

Draft requirements are very specific and just like ductwork you can't just hookup some pipe and hope it works.

What are the btu inputs of the appliances? How much vertical height, how much horizontal distances??

"Danger Will Robinson"
We actually didn't determine any sizes yet. We were using 6" as a hypothetical for pricing materials, etc. The vent pipes from the water heaters are 3", and from the furnaces are 5". Vertical runs are about 2 feet for each unit, horizontal about 3 feet.

Quote:
Originally Posted by beenthere View Post
Use wyes to tie each units vent to the liner.

6" liner may or may not be big enough. So ask him how he determined size.
Wyes sound wise So I'll have the tee coming into the basement, then from there I'll have a quantity of 4 wyes.

Quote:
Originally Posted by hvac benny View Post
Unless you're a ticketed gas fitter, you should not be doing this work. I'm all for DIY, even when it comes to gas, but this sounds like a rental to me. Home owners can pull permits where I live, but only if it's their own single family home that they live in, they are doing the work themselves, and aren't paying anyone to do the work (ie. you have a right as a home owner to possibly endanger yourself and immediate family, but no one else). The scope of work is beyond what you can or should do.
Second unit is vacant. Not sure if that makes a difference or not. But the process seems simple and straightforward. My friend whose house it is said that the questions about size of the liner and what configuration to use to set everything up correctly would be answered by the company that's supplying the liner. I just wanted to get the opinion of some other pros.

Quote:
Originally Posted by COLDIRON View Post
Looks like a double Chimney setup, why not run two liners one for each house. He's still saving big $$$$.
Only one house & one chimney (two units in the house - one above the other), so I could be wrong but I think there's only room for one liner.
Chris Sweeney is offline   Reply With Quote
Old 10-11-2012, 04:08 PM   #7
REP
Member
 
Join Date: Jul 2011
Posts: 615
Rewards Points: 500
Default

4 ducts going to chimney, or 1?


If it were me,I'd use two chimeny liners (one for each unit).Still size is a must and nothing is close enough.
You didn't say how high the chimey is nor what size the inside of the chimey is.
REP is offline   Reply With Quote
The Following User Says Thank You to REP For This Useful Post:
COLDIRON (10-11-2012)
Old 10-11-2012, 06:02 PM   #8
Member
 
Join Date: Apr 2012
Location: Glenside, PA
Posts: 82
Rewards Points: 75
Default

4 ducts going to chimney, or 1?


Quote:
Originally Posted by REP View Post
If it were me,I'd use two chimeny liners (one for each unit).Still size is a must and nothing is close enough.
You didn't say how high the chimey is nor what size the inside of the chimey is.
If I had two liners, I'd still have to vent two units into each liner. What's wrong with four units into one liner (as it is now)? I could be wrong, but it's not like both furnaces and both water heaters will all be running simultaneously, and even if they did, why wouldn't one liner be able to handle it.

Remember, there's only one chimney, so if I put in two liners, they would have to be two smaller liners. So instead of putting in, say, one 6" liner, I'd have to put in two 3" liners. Doesn't really make sense logically to me, not to mention the added cost, but then again I'm no HVAC/chimney expert.
Chris Sweeney is offline   Reply With Quote
Old 10-11-2012, 06:45 PM   #9
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,458
Rewards Points: 4,562
Default

4 ducts going to chimney, or 1?


It would probably be more like 2-5" liners, if you went with 2.

What is the combined total BTU input of all the water heaters and both furnaces.

You will be surprised how often all 4 run at the same time. Generally only on the colder days.
beenthere is online now   Reply With Quote
Old 10-11-2012, 08:33 PM   #10
Member
 
Join Date: Apr 2012
Location: Glenside, PA
Posts: 82
Rewards Points: 75
Default

4 ducts going to chimney, or 1?


Quote:
Originally Posted by beenthere View Post
It would probably be more like 2-5" liners, if you went with 2.

What is the combined total BTU input of all the water heaters and both furnaces.

You will be surprised how often all 4 run at the same time. Generally only on the colder days.
Right, I was just using 6" (or 2-3") as a example/starting point. Not sure of the combined BTUs (I'm not at my friend's house until tomorrow), but I will check. Once I figure out the BTUs of each unit and figure the total combined BTUs, how should I use that in choosing the width of the liner? Is there a formula to follow or something?
Chris Sweeney is offline   Reply With Quote
Old 10-11-2012, 09:57 PM   #11
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,458
Rewards Points: 4,562
Default

4 ducts going to chimney, or 1?


There are charts. it goes by total BTU, longest lateral, and height of chimney/liner.

Advertisement

beenthere is online now   Reply With Quote
Reply


Thread Tools
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
How to install chimney liner Rockford How To Guides 3 07-16-2012 05:15 PM
Why a Chimney Liner? Rockford HVAC 0 07-12-2012 11:03 AM
How To Install a Chimney Liner Rockford How To Guides 0 01-24-2012 11:00 AM
Looks like leaking around the chimney - roofer says it is the chimney itself Salvatorparadise Roofing/Siding 6 03-07-2008 04:12 PM




Top of Page | View New Posts