I have an 45K BTU Hanging LP Heater on the way and getting ready to install. Need help with with what I need for the venting. I know I need 4" galvanized/SS. It'll be a horizonatal vent, about 5 ft max length directly out the back of the garage. I'll need a Wind Cap due to back of garage being west facing. Went to Lowes and they weren't much help. They have 4" vent pipe and a Rain Cap. The Rain Cap is for 6" but guy said I could use a 4">6" adapter... Would this work for a rain cap? What is required for pipe going through garage wall (regular framing with vinyl siding). Do I need a special flange? Piece of double wall, etc? Lastly, for residential install vent runs downhill from heater, for commercial it runs up hill. Why? Does it matter? Garage is detached and I won't be pulling permits... Thanks in advance for help...
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LP Garage Heater Install Questions
- Thread starter Gunnert
- Start date
1953mercury
Well-known member
Are you sure it can be vented horizontally?? You should check install directions when you get it or get them on line. They should include a venting chart with allowable horizontal runs, but you will still need to go vertical outside unless it is power vented unless I am much mistaken. Mike
dave67fd
Well-known member
Yes, It can be vented horizontally as long as it is installed per the manuf. specifications and it is a power vented unit.
If you have the manual it will tell you what is required/recommended for that heater. b-vent, wall thimble t trap, rain cap termination etc..
You can buy the kit or individual pieces but still going to cost you abit if you want to do it correctly. New cat III requires it. If you don't care about codes install how you wan't and accept responsibility.
The vent pitch is vertical for residential installations. Depending on how your town classifies your garage. If detatched it can be consider commercial if it's not attached to a living space but your town may classify it as residential zoning regardless. Vertical or horizontal condensate drain will depend on that classification.
If you have the manual it will tell you what is required/recommended for that heater. b-vent, wall thimble t trap, rain cap termination etc..
You can buy the kit or individual pieces but still going to cost you abit if you want to do it correctly. New cat III requires it. If you don't care about codes install how you wan't and accept responsibility.
The vent pitch is vertical for residential installations. Depending on how your town classifies your garage. If detatched it can be consider commercial if it's not attached to a living space but your town may classify it as residential zoning regardless. Vertical or horizontal condensate drain will depend on that classification.
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samert111
Well-known member
Duane,
I'm currently doing the exact same thing except mine is a 75K Beacon Morris BRT furnace. I'm using their seperate combustion kit which brings the combustion air for the furnace in from outside thru their concentric box.
What you need is a 4" B vent pipe and thimble thru the wall which will give you the correct clearances (1") from combustables. Use some Hi-temp silicone on both sides of the thimble around the "B" vent to seal up the small air gap. Pitch it down 1/4" per foot. For that short of a run I would use one 5ft pc of the "B" vent all the way to the heater.
If you have a Menards in your area, they have a good varity of what you need. Assuming you can go straight out the wall without any bends, following are links to the 4 pcs you would need I think.
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-wall-thimble-4/p-1707981-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-draft-hood-4/p-1707971-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-pipe-4-x-5/p-1707969-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-rain-cap-4/p-1902166-c-9462.htm
I'm currently doing the exact same thing except mine is a 75K Beacon Morris BRT furnace. I'm using their seperate combustion kit which brings the combustion air for the furnace in from outside thru their concentric box.
What you need is a 4" B vent pipe and thimble thru the wall which will give you the correct clearances (1") from combustables. Use some Hi-temp silicone on both sides of the thimble around the "B" vent to seal up the small air gap. Pitch it down 1/4" per foot. For that short of a run I would use one 5ft pc of the "B" vent all the way to the heater.
If you have a Menards in your area, they have a good varity of what you need. Assuming you can go straight out the wall without any bends, following are links to the 4 pcs you would need I think.
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-wall-thimble-4/p-1707981-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-draft-hood-4/p-1707971-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-pipe-4-x-5/p-1707969-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-rain-cap-4/p-1902166-c-9462.htm
I'm also looking into what is involved for installation of a natural gas garage heater. I came across this publication on Modine's site for venting: http://www.modine.com/web_server_content/en_us/publication/building_HVAC/White_Paper_76-801.pdf
Looks like maybe this applies more to Residential applications, so depending on how your detatched garage is classified it may not apply.
Looks like maybe this applies more to Residential applications, so depending on how your detatched garage is classified it may not apply.
Duane,
I'm currently doing the exact same thing except mine is a 75K Beacon Morris BRT furnace. I'm using their seperate combustion kit which brings the combustion air for the furnace in from outside thru their concentric box.
What you need is a 4" B vent pipe and thimble thru the wall which will give you the correct clearances (1") from combustables. Use some Hi-temp silicone on both sides of the thimble around the "B" vent to seal up the small air gap. Pitch it down 1/4" per foot. For that short of a run I would use one 5ft pc of the "B" vent all the way to the heater.
If you have a Menards in your area, they have a good varity of what you need. Assuming you can go straight out the wall without any bends, following are links to the 4 pcs you would need I think.
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-wall-thimble-4/p-1707981-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-draft-hood-4/p-1707971-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-pipe-4-x-5/p-1707969-c-9462.htm
http://www.menards.com/main/heating-cooling/venting/b-vent/class-b-rain-cap-4/p-1902166-c-9462.htm
THANKS for speaking in a language I understand. Located in Northern Virginia, closest Menard's is Ohio. Heater I have coming is a 45K ProCom, LP; couldn't resist the Northern Tools sale price... There are no local distributors with a 4" vent thimble. I'll have to order one.
Is there a minimum distance the vent has to run outside the garage or can I attach a rain cap directly to the thimble? Vent will exit under eave but there is no ventilation from eave into garage; have spray foam insulation sealing the eaves...
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samert111
Well-known member
Is there a minimum distance the vent has to run outside the garage or can I attach a rain cap directly to the thimble?
Yes, there is a mininimum distance the vent has to extend past the exterior of your building. The instructions that will come with your heater will explain. You do not want it too close or it can damage your siding, especially in your case since it will be facing into the prevailing winds from the West. I'm thinking you would want it at least 2-3 feet. This is a good reason to have it inspected.
Vent will exit under eave but there is no ventilation from eave into garage; have spray foam insulation sealing the eaves.
This comment leads me to ask if the ceiling in your garage is finished and insulated above the ceiling? If so how is it vented up into there to moisture issues? Most buildings either have soffit or gable vents that work in conjunction with a roof ridge vent or pot vents to keep air moving.
Just asking!
Was that a type-o where is says 19' ft ceiling height? Wow, that's more like barn than detached garage. Your 45K Btu heater likely not enough for 28' x 33' with a 19 foot tall ceiling??
Any pictures? What specific hanging heater are you getting?
Any pictures? What specific hanging heater are you getting?
Yes, there is a mininimum distance the vent has to extend past the exterior of your building. The instructions that will come with your heater will explain. You do not want it too close or it can damage your siding, especially in your case since it will be facing into the prevailing winds from the West. I'm thinking you would want it at least 2-3 feet. This is a good reason to have it inspected.
This comment leads me to ask if the ceiling in your garage is finished and insulated above the ceiling? If so how is it vented up into there to moisture issues? Most buildings either have soffit or gable vents that work in conjunction with a roof ridge vent or pot vents to keep air moving.
Just asking!
Detached garages don't require venting in the ceiling. My walls are 9' and the ceiling peaks at 19'. Ceiling is open rafters and matches the pitch of the house. I ran the numbers on volume and sqft and 35k BTU is recommended. I'm going with 45K. The spray foam really adds to the sealing up of the garage and heat/cool retention. I can now warm the garage with a kerosene and make it tolerable. I have a 60" ceiling fan hung from the top which helps push the heat down.
The ProCom unit is like the Big Maxx or Hot Dawg, low profile....
I ordered a Horizontal Vent Kit (4") this afternoon.
Can anyone tell me why for one installation vent runs uphill and for another downhill? What's the point?
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samert111
Well-known member
Detached garages don't require venting in the ceiling. My walls are 9' and the ceiling peaks at 19'. Ceiling is open rafters and matches the pitch of the house. I ran the numbers on volume and sqft and 35k BTU is recommended. I'm going with 45K. The spray foam really adds to the sealing up of the garage and heat/cool retention. I can now warm the garage with a kerosene and make it tolerable. I have a 60" ceiling fan hung from the top which helps push the heat down.
The ProCom unit is like the Big Maxx or Hot Dawg, low profile....
I ordered a Horizontal Vent Kit (4") this afternoon.
Can anyone tell me why for one installation vent runs uphill and for another downhill? What's the point?
I missed the part in your signature about the 8" spray foam ceiling.
Sorry, I can't answer your question on the uphill vs. downhill. My instructions only show down hill (1/4" per foot slope). May have something to do with commercial vs. residential. I would go down hill because any condensation in the vent pipe I would want to run away from my heater.
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