Hi guys new to the forum and did a little search the last couple days and really cant find a answer to my particular question. I have a attached garage and where i want to hang the heater and put the vent thru the garage ceiling and up into the attic. roughly 7-8 feet away is a chimney from our decorative gas fireplace. the chimney is 14" dia. my question is can i tap into the chimney to vent the exhaust for my mr heater. any help would be appreciated
Mr heater venting question
- Thread starter mrhino
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uniballer
Well-known member
Depends on local codes, but in va you can do it.
I'm going to say no. Assuming you want to be code compliant.
My answer also is assuming it has fan assisted draft. (A draft inducer). Theres a lot of variables. Personally I would run a new chimney for it.
I guess im not going to tap into the existing chimney. Im going to run it right next to it. I have the 45k unit Im confused with the directions. what size pipe should i be using? the instructions say 3" but the pipe kit they want to sell you is in 4" I realize it is made for both the 45k and the 75K. can I run the 3" and should it be B vent or should it just be B vent while its in the attic.
nwav8tor
Well-known member
I sure they make both 3" and 4" vent kits for Mr Heaters. My 75,000 unit needed 4" but I've seen 3" kits on Amazon. The B-vent is required in unheated spaces but I used it for my entire run.
Paul
Paul
dave67fd
Well-known member
Your Mr Heater requires a 3" vent connector.
You can also vent out through your chimney, but your local codes take juristiction.
All this info is in your manual. You should read it about 10 times, then read again10 more. lol
The unit may be vented vertically as a single appliance or as
a common vent with other gas-fired appliances. In common
venting situations, vent connectors for other appliances
must maintain a 4” (100mm) vertical separation between
the vent connectors. Refer to common venting tables in the
(American) National Fuel Gas Code ANSI Z223.1 or (Canada)
CSA B149.1 Natural Gas and Propane Installation Code for
proper vent size.
You can also vent out through your chimney, but your local codes take juristiction.
All this info is in your manual. You should read it about 10 times, then read again10 more. lol
The unit may be vented vertically as a single appliance or as
a common vent with other gas-fired appliances. In common
venting situations, vent connectors for other appliances
must maintain a 4” (100mm) vertical separation between
the vent connectors. Refer to common venting tables in the
(American) National Fuel Gas Code ANSI Z223.1 or (Canada)
CSA B149.1 Natural Gas and Propane Installation Code for
proper vent size.
For research I've done planning on my own install (ie either MHU45NG or HSU45NG), I've found that double-wall pipe should be used for vertical through ceiling and roof (and code requires 2 feet above roof to cap). My plan is to use 3" vertical flue (double-wall where code requires) so don't have to cut through brick walls of my garage if I were to do horizontal flue. Also will use insulation guard above ceiling so any blown insulation can't pile up next to the fluepipe.
Any one use Uni-strut to install? I went to wholesale shop and they've got a huge one (almost 2 inches) and also a smaller size (little over 1 inch). He also said I could use special spring-loaded nuts that just take a half turn to connect to the Uni-strut. Any example pictures of successful installs as Uni-strut sounds like the way to go?
Any one use Uni-strut to install? I went to wholesale shop and they've got a huge one (almost 2 inches) and also a smaller size (little over 1 inch). He also said I could use special spring-loaded nuts that just take a half turn to connect to the Uni-strut. Any example pictures of successful installs as Uni-strut sounds like the way to go?
The 14" vent from the gas fireplace is in all likely hood a vent specific to to the fireplace and as such there will be no way to legally or safely use it as a common vent.
I don't know what the vent "kits" include but I would much prefer buying B-vent from a local source that has everything in stock, that way I can get the exact lengths I need plus extras and return whats not needed.
I used Super-Strut for my 45K unit. I got everything at Home Depot. I used the spring loaded nuts and 3/8 threaded rod to install.
I just bought my venting yesterday and will start installing today hopefully. I am going with 3" B vent all the way. Next I'll be trenching the gas line from the house.
Attachments
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dave67fd
Well-known member
I did the same way. I used stainless just because we had a bunch at work.
Steevo
Well-known member
Uni-strut to hang mine, too.
And B-vent all the way to the cap.
And B-vent all the way to the cap.
Nice installs with Uni-strut and great quality venting. Thanks for pics.
Hope to soon be trenching about 20 feet for my underground yellow plastic NG line to garage. Anyone with knocks against Stab-lock connectors for physical connection of yellow plastic pipe to the upright steel risers? Most plumbers here only do Stab-lock as don't have fuser machines. Comments?
Hope to soon be trenching about 20 feet for my underground yellow plastic NG line to garage. Anyone with knocks against Stab-lock connectors for physical connection of yellow plastic pipe to the upright steel risers? Most plumbers here only do Stab-lock as don't have fuser machines. Comments?
Guys, how did you connect the vent to the back of the heater. Did you add a couple sheet metal screws to keep it in place or use tape or?
Also, I see some of you are using a firestop plate where it goes through the ceiling. I was going to just use one half of a wall thimble. Any problem with this?
Also, I see some of you are using a firestop plate where it goes through the ceiling. I was going to just use one half of a wall thimble. Any problem with this?
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mrobins297aaa
Well-known member
you can screw it where it connects to the heater, thats the only place you can put screws in it..............don't use tape
nwav8tor
Well-known member
mrobins297aaa
Well-known member
if you screw the pipe in any place other than where it connects to the applaince you will lose the UL rating on it.
dave67fd
Well-known member
I have a single wall 90 which is screwed to the flue transistion with three screws. The 90 is then connected to the b-vent with three longer screws and are used to lock the single to b-vent only. You don't wan't to distort the b-vent. Use silastic or similar to seal the annular area of the b-vent.
I'm sure your local codes require a firestop plate.
http://www.checkthishouse.com/qa/194/how-to-join-b-vent-and-single-wall-pipe
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nwav8tor
Well-known member
The firestop I used is also a support to counter the weight of the vertical stack.
I also used a special piece that is designed to transition from single wall pipe to B-pipe. The transition already has the annular opening of the B-pipe sealed so there was no need for me to do that. All I had to do was screw the single-wall end of the transition to the adapter pipe that came with the Mr Heater and then add a B-vent elbow and five feet of straight B-vent through the ceiling, attic and roof.
All very clean and simple!
Paul
I also used a special piece that is designed to transition from single wall pipe to B-pipe. The transition already has the annular opening of the B-pipe sealed so there was no need for me to do that. All I had to do was screw the single-wall end of the transition to the adapter pipe that came with the Mr Heater and then add a B-vent elbow and five feet of straight B-vent through the ceiling, attic and roof.
All very clean and simple!
Paul