I purchased a 75,000 btu Reznor heater and it has a 5.5" x 4" oval vent. I have 2 questions, 1) can this be vented through the wall instead of through the roof and 2) do you squeeze a round pipe onto the oval vent or do you have to get an adapter? Any install advice will be great. I am trying to do all the work I can myself so the plumber only has to check the gas line and vent hookups. Thanks...Mike
"B" vent through wall
- Thread starter mikec35
- Start date
1) It depends on the installation manual. Is it a direct vent appliance?
2) A short piece of single wall can be put on the oval.
As far a B-vent through the wall for a direct vent application, no. It is not certified for whats referred to as Category 3 installations which basically means the vent is under a positive pressure. If the heater is rated category 1 or 3 you can pass B-vent thru a wall as long as it connects to a proper chimney.
Tim The Tool Man
Well-known member
I have a similar (maybe the same?) 75,000 Reznor with the optional power vent. It is plumbed horizontally out the sidewall of my shop. Been that way for many years with no issues...
I did repaint it from the ugly factory pink and yes it it too close to the back wall (12" not the recommended 24") but that is a service access spec. not a fire code spec. and I didn't want to be bumping my head on the thing as I walked by...
I did repaint it from the ugly factory pink and yes it it too close to the back wall (12" not the recommended 24") but that is a service access spec. not a fire code spec. and I didn't want to be bumping my head on the thing as I walked by...
danski0224
Well-known member
Type B vent is not classified for horizontal venting.
I'm not exactly sure that this is a type B vent... that is what someone told me. I actually think it might be direct vent...Hopefully the manufacturer will send me the instruction manual soon and I will know for sure. Thanks for all the advice.
nehog
Well-known member
That document doesn't say very much, but only mentions Category 1 appliances, not Category 3. It is also for Canada, not the US.
Its a Reznor XL75-3. I just located an owners manual, it says you can vent horizonally. I will vent horizontally outside the side wall then up through a chimney pipe. It is a 5 inch oval vent. Wonder if I can downsize to a 4" chimney pipe or if I should go up to a 6" pipe, I can't seem to find a 5" pipe.
nehog
Well-known member
Try Grainger for the 5" pipe... That is where I got mine.
Reznor has a great website so I'd dig through looking for a horizontal vent kit. Also you could "mystery shop" to a Reznor certifed installer and talk shop over the phone. If unit is new enough to be power vented, and without a standing pilot (ie electronic ignition), then sounds like double-wall vent horizontal out through wall is all you need. Likely unnecessary to extend pipe up outside building . . . . just a horizontal cap on outside of building.
FYI for your install, be careful of local codes as my local KS code will NOT allow install like Tim The Toolman as they are afraid vehicle can hit heater tearing if off wall and creating gas leak. They only allow installs ABOVE level of garage door rails.
FYI for your install, be careful of local codes as my local KS code will NOT allow install like Tim The Toolman as they are afraid vehicle can hit heater tearing if off wall and creating gas leak. They only allow installs ABOVE level of garage door rails.
Menard's also has 5" pipe.
Like Tim, I also installed my Reznor and horizontally vented it, but it is an FE75 and has the power venter so I am good by code. Mine is a 4" round exhaust...but as I was shopping for my B-type chimney pieces, I saw a LOT of 5" B-type at Menard's if you have one near you.
Just installed mine this past weekend...here are a few pics...(yes, I froze my @$$ off...and my hands didn't fare any better!! But my garage is nice and warm when I want it!!!)
The cord is temporary until I get my garage sub-panel wired...that is in-flight.
Like Tim, I also installed my Reznor and horizontally vented it, but it is an FE75 and has the power venter so I am good by code. Mine is a 4" round exhaust...but as I was shopping for my B-type chimney pieces, I saw a LOT of 5" B-type at Menard's if you have one near you.
Just installed mine this past weekend...here are a few pics...(yes, I froze my @$$ off...and my hands didn't fare any better!! But my garage is nice and warm when I want it!!!)
The cord is temporary until I get my garage sub-panel wired...that is in-flight.
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I ran a thermostat...but just a simple 2-wire one...cheapie from HD. That way I can get some regulated heat and don't have to keep going over to shut it down.
You can see the tiny dark wire in the next few photos in the rafters of the bonus room above the garage...
I have already found if I set it on 60, it is almost too warm in there for doing physical work...but I guess once the renovation stuff is done and I am just working on my bikes or on a car, it may need a few more degrees...
The other thing I have going for me is my bonus room above the garage is unfinished so it makes it easy for me to access wiring, etc. That made it easy for me to wire the thermostat!
Let me know if you have any other questions, Mike. And I would say double-check your code requirements to determine if you can vent that horizontally without a powervent installed...I don't think so but I am NOT the expert here...there are a LOT of others who can answer that better than I can.
- Chip
You can see the tiny dark wire in the next few photos in the rafters of the bonus room above the garage...
I have already found if I set it on 60, it is almost too warm in there for doing physical work...but I guess once the renovation stuff is done and I am just working on my bikes or on a car, it may need a few more degrees...
The other thing I have going for me is my bonus room above the garage is unfinished so it makes it easy for me to access wiring, etc. That made it easy for me to wire the thermostat!
Let me know if you have any other questions, Mike. And I would say double-check your code requirements to determine if you can vent that horizontally without a powervent installed...I don't think so but I am NOT the expert here...there are a LOT of others who can answer that better than I can.
- Chip
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nwav8tor
Well-known member
I ran a thermostat...but just a simple 2-wire one...cheapie from HD. That way I can get some regulated heat and don't have to keep going over to shut it down.
You can see the tiny dark wire in the next few photos in the rafters of the bonus room above the garage...
I have already found if I set it on 60, it is almost too warm in there for doing physical work...but I guess once the renovation stuff is done and I am just working on my bikes or on a car, it may need a few more degrees...
The other thing I have going for me is my bonus room above the garage is unfinished so it makes it easy for me to access wiring, etc. That made it easy for me to wire the thermostat!
Let me know if you have any other questions, Mike. And I would say double-check your code requirements to determine if you can vent that horizontally without a powervent installed...I don't think so but I am NOT the expert here...there are a LOT of others who can answer that better than I can.
- Chip
Chip, Why didn't you just vent straight up through the roof? Seems like it'd be much easier and less expensive then the way you went. If you're planning to insulate, it'd also be easier to keep the insulation the required distance away from the vent.
Just Curious,
Paul
Paul,
I decided to go thru the wall because I have a 12/12 roof and would have needed a 15+ ft chimney to meet code and clear my roof properly...believe me, I wrestled with options for quite some time and researched local code...even spoke with twp building inspector before settling on this choice. I probably would have preferred to go up, but it was going to be a science project. ;-)
I decided to go thru the wall because I have a 12/12 roof and would have needed a 15+ ft chimney to meet code and clear my roof properly...believe me, I wrestled with options for quite some time and researched local code...even spoke with twp building inspector before settling on this choice. I probably would have preferred to go up, but it was going to be a science project. ;-)
nwav8tor
Well-known member
Chip, I copied this from Duravent.com:
VENT TOP INSTALLATION
The location selected for the vent top can have a
significant influence on proper draft performance. On a
windy day, nearby obstructions such as a wall or tree can
create a zone of high pressure. When the vent cap is
located in these high pressure zones, the vent becomes
highly susceptible to windy conditions and may tend to
backdraft. In those cases when the vent must be installed
in a position less than 8 feet from a wall, parapet, or other
obstruction, the vent cap must be located at least 2 feet
above the obstruction.
High pressure zones can also be created by wind striking
the roof itself. For roofs from flat to 7/12 pitch, the vent
cap should be positioned at least 1 foot above the roof
surface. As indicated in Figure 43, measure the vertical
distance between the roof surface and the lowest discharge
opening on the vent cap.
As the roof pitch increases above 7/12, the roof begins to
act more like a wall, and the pressure zone increases. To
compensate for this, it is necessary to increase the height of
the vent. The steeper the roof, the greater the vent height
required to avoid the high pressure zone. Refer to the table
in Figure 43 listing minimum heights for roof pitches
greater than 7/12.
Figure 43
Gas Vent Termination Table
Roof Pitch........................Minimum Height
Flat to 7/12 . . . . . . . . . . . 1.0 feet*
Over 7/12 to 8/12 . . . . . . . . . 1.5 feet
Over 8/12 to 9/12 . . . . . . . . . 2.0 feet
Over 9/12 to 10/12. . . . . . . . . 2.5 feet
Over 10/12 to 11/12 . . . . . . . 3.25 feet
Over 11/12 to 12/12 . . . . . . . . 4.0 feet
Over 12/12 to 14/12 . . . . . . . . 5.0 feet
Over 14/12 to 16/12 . . . . . . . . 6.0 feet
Over 16/12 to 18/12 . . . . . . . . 7.0 feet
Over 18/12 to 20/12 . . . . . . . . 7.5 feet
Over 20/12 to 21/12 . . . . . . . . 8.0 feet
* This requirement covers most installations
For gas vents 12 inches in size or smaller, the vents may
terminate in accordance with the minimum heights listed in
Figure 43 provided they are at least 8 feet from a vertical
wall or similar obstruction. All other gas vents must
terminate not less than 2 feet higher than any portion of a
building within 10 feet.
From the looks of your install, your vertical vent should've been more than 8' from a vertical wall and would have only required 4' above the roof penetration. What requirements were your inspectors quoting?
Paul
VENT TOP INSTALLATION
The location selected for the vent top can have a
significant influence on proper draft performance. On a
windy day, nearby obstructions such as a wall or tree can
create a zone of high pressure. When the vent cap is
located in these high pressure zones, the vent becomes
highly susceptible to windy conditions and may tend to
backdraft. In those cases when the vent must be installed
in a position less than 8 feet from a wall, parapet, or other
obstruction, the vent cap must be located at least 2 feet
above the obstruction.
High pressure zones can also be created by wind striking
the roof itself. For roofs from flat to 7/12 pitch, the vent
cap should be positioned at least 1 foot above the roof
surface. As indicated in Figure 43, measure the vertical
distance between the roof surface and the lowest discharge
opening on the vent cap.
As the roof pitch increases above 7/12, the roof begins to
act more like a wall, and the pressure zone increases. To
compensate for this, it is necessary to increase the height of
the vent. The steeper the roof, the greater the vent height
required to avoid the high pressure zone. Refer to the table
in Figure 43 listing minimum heights for roof pitches
greater than 7/12.
Figure 43
Gas Vent Termination Table
Roof Pitch........................Minimum Height
Flat to 7/12 . . . . . . . . . . . 1.0 feet*
Over 7/12 to 8/12 . . . . . . . . . 1.5 feet
Over 8/12 to 9/12 . . . . . . . . . 2.0 feet
Over 9/12 to 10/12. . . . . . . . . 2.5 feet
Over 10/12 to 11/12 . . . . . . . 3.25 feet
Over 11/12 to 12/12 . . . . . . . . 4.0 feet
Over 12/12 to 14/12 . . . . . . . . 5.0 feet
Over 14/12 to 16/12 . . . . . . . . 6.0 feet
Over 16/12 to 18/12 . . . . . . . . 7.0 feet
Over 18/12 to 20/12 . . . . . . . . 7.5 feet
Over 20/12 to 21/12 . . . . . . . . 8.0 feet
* This requirement covers most installations
For gas vents 12 inches in size or smaller, the vents may
terminate in accordance with the minimum heights listed in
Figure 43 provided they are at least 8 feet from a vertical
wall or similar obstruction. All other gas vents must
terminate not less than 2 feet higher than any portion of a
building within 10 feet.
From the looks of your install, your vertical vent should've been more than 8' from a vertical wall and would have only required 4' above the roof penetration. What requirements were your inspectors quoting?
Paul
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Paul,
Yep...that's exactly what my twp inspector said...except his interpretation was 10' from the vertical...
So this is how he told me to go about calculating my clearance:
He told me to take a measurement of a 10' radius from the chimney exit from my roof (imagine tying a string around the chimney and making it 10' long) and when I got to a place on my roof that I wouldn't hit the roof with the string, I then need to go 5' higher than that. Well, I just inverted the measurement technique (since my roof was covered with snow) and took a 10 foot measurement from my chimney (where it would exit the roof) from the inside of my attic and then looked up...which put me right at the roof ridge vent...so I would have to go 5 ft higher than my ridge vent and that would have me with a ridiculously tall chimney sticking out of my roof...so I opted for the side vent. That is exactly how he told me to measure it...which didn't make sense to me because I looked at my gas fireplace chimney which comes out on the back side of my roof and it isn't taller than my roof line and is only a few feet away from the roof...it is about 4'-6' tall, but it definitely doesn't comply with the way he told me to measure...maybe because it is a gas fireplace? I don't know...so I just did what I was told...
I did consider going up the inside of my roof and then out the top and only have a 5'-7' chimney, and may still do that come spring, but for now, this is my working solution.
Yep...that's exactly what my twp inspector said...except his interpretation was 10' from the vertical...
So this is how he told me to go about calculating my clearance:
He told me to take a measurement of a 10' radius from the chimney exit from my roof (imagine tying a string around the chimney and making it 10' long) and when I got to a place on my roof that I wouldn't hit the roof with the string, I then need to go 5' higher than that. Well, I just inverted the measurement technique (since my roof was covered with snow) and took a 10 foot measurement from my chimney (where it would exit the roof) from the inside of my attic and then looked up...which put me right at the roof ridge vent...so I would have to go 5 ft higher than my ridge vent and that would have me with a ridiculously tall chimney sticking out of my roof...so I opted for the side vent. That is exactly how he told me to measure it...which didn't make sense to me because I looked at my gas fireplace chimney which comes out on the back side of my roof and it isn't taller than my roof line and is only a few feet away from the roof...it is about 4'-6' tall, but it definitely doesn't comply with the way he told me to measure...maybe because it is a gas fireplace? I don't know...so I just did what I was told...
I did consider going up the inside of my roof and then out the top and only have a 5'-7' chimney, and may still do that come spring, but for now, this is my working solution.
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nwav8tor
Well-known member
Yea, sometimes inspectors can make you jump through hoops that really shouldn't have to be jumped through!!!
Your 10' radius string from the vent (really only should be 8') is only to see if there is a vertical wall within that distace from the vent. If there is, then the vent must terminate at least 2' higher than the top of the verical wall/obstruction. If there is no vertical wall/obstruction (just the roof itself), then the vent can terminate according to that termination height vs roof pitch table (even if it terminates below the roof's ridge line).
Caveat: Your twp may have imposed more strict requirements than normal.
Paul
Your 10' radius string from the vent (really only should be 8') is only to see if there is a vertical wall within that distace from the vent. If there is, then the vent must terminate at least 2' higher than the top of the verical wall/obstruction. If there is no vertical wall/obstruction (just the roof itself), then the vent can terminate according to that termination height vs roof pitch table (even if it terminates below the roof's ridge line).
Caveat: Your twp may have imposed more strict requirements than normal.
Paul
Thanks, Paul...I wondered if that was what it really meant as I have done a great deal of research and came across that explanation a number of times, but he specifically said it (the imaginary string) couldn't hit the roof...and since I didn't feel qualified to argue with him, I did what I knew was safe, and within code.
Oh well...no worries, I have heat in my garage!! Now I have to get going on fixing cracking ceiling tape joints and sand all my hole fills, get the place painted so I can get to work on the bikes!!
Oh well...no worries, I have heat in my garage!! Now I have to get going on fixing cracking ceiling tape joints and sand all my hole fills, get the place painted so I can get to work on the bikes!!
My dad gave me 4 sections of insulated stainless 6" stove pipe. It is pretty heavy. I will use this and go from the front corner of my garage to the ridge and out through the roof. Do I need to use a cathedral ceiling support box? Thanks
Mike, I would say no, but I am not an expert. I would use the same chimney tube supports I used if they have them for 6" pipe...just screw them to your rafter making sure they provide the right vector of support (Angled upwards or straight up, as opposed to sideways or from below, etc.
).I included a picture of mine so you can see what they look like. Hopefully this will help...
nwav8tor
Well-known member
Check with Reznor for your heater's requirements, but I believe that stove pipe is just for wood or pellet burning stoves and should not be used to vent natural gas or propane heaters.
My non-expert .02 worth,
Paul
Thanks for the replies... I am starting to think this double wall insulated pipe is for a vertical install only, it is stainless and pretty heavy. I am going to get a lighter weight 5 or 6 inch pipe. Did you guys use single or double wall pipe? Single wall 6 inch black pipe is readily available at Lowes. How far does single wall have to be away from combustibles?