Hello. I just purchased a Mr Heater Big Max 80K BTU Garage Heater and will be using Propane. My question is what type of termination cap is allowed for the CAT3 type venting. The manual only shows a T Pipe that is open on both ends. Are there other type termination caps I can use that are safe? My concern is with just an open pipe will air just be coming into the garage when the unit is not running and alot of hot air coming in during the summer? Is there a different type of termination cap that I can use that has a flap or something to keep air from coming back in garage or water running back towards unit when its raining since pipe slopes down into garage. Any help and pics would be greatly appreciated. Thanks
Mr Heater Big Max 80K BTU Allowable Horizontal Termination Caps
- Thread starter Skip707
- Start date
bobbyjean
Well-known member
supply house.com sells z-vent..think they may have something that looks like a dryer vent termination
dave67fd
Well-known member
You want a cat III termination cap for Horizontal vent. Google it for choices. Duravent is a popular choice.
You should be following fig. 6 in the manual (link attached) for Horizontal Residential venting (assuming your not a commercial buisness or zoned as such). Regardless, you could check with your state and local codes first as they take jurisdiction over anything else (that is if you have any plans to do it by code).
Although my heater/Install is a bit older and the cat III requirement doesn't apply, the dimensions and look are the same.
https://www.northerntool.com/images/downloads/manuals/27456.pdf
You should be following fig. 6 in the manual (link attached) for Horizontal Residential venting (assuming your not a commercial buisness or zoned as such). Regardless, you could check with your state and local codes first as they take jurisdiction over anything else (that is if you have any plans to do it by code).
Although my heater/Install is a bit older and the cat III requirement doesn't apply, the dimensions and look are the same.
https://www.northerntool.com/images/downloads/manuals/27456.pdf
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metschers
Well-known member
Skip
I had the same problem. After several hours of research, I went with a kit from gadgetsgo.com. It included the everything needed, including a backdraft flap. Plus it was an all stainless steel kit(flex vent)Ordered, 2 day delivery.
Saved me a lot of $$$$$$.
Hope that helps you out,
SM
I had the same problem. After several hours of research, I went with a kit from gadgetsgo.com. It included the everything needed, including a backdraft flap. Plus it was an all stainless steel kit(flex vent)Ordered, 2 day delivery.
Saved me a lot of $$$$$$.
Hope that helps you out,
SM
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MrSurly
Well-known member
MUST
KNOW
MORE!
I really like the look of that boot!
Tell me more, link to your specific kit, please.
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metschers
Well-known member
MrSurly,
Here's the link...https://gadgetsgo.com/2ZVWB04-Wall-Hung-4-inch-Vent-Kit-Stainless-Steel-Tankless.html
Actually it's still on sale for $169.88 free shipping ( I opted for 2-day express delivery 5.00).
The boot/wall thimble is flat, so I used a couple of 1x1 clamped in a vice and made my bents to match the contour of the corrugated steel siding on the outside. On the inside, I left the thimble flat and built a spacer out of 2x6 to protect the insulation. The wall thimble is 2 pieces that are telescopic so they fit together very tightly. Surrounded by the 2x6 "box", it forms a double walled transition thru the wall. Once together the outside dryer vent looking piece slides on and clamps. The 4"dia kit(Z-vent) is all stainless with internal gaskets on each piece. I used a little lithium grease on the gaskets for easier assembly figured it would burn off. Also wear gloves, the pieces are very sharp. The kit included a 90 degree elbow, but I needed a 45. I called and talk to Ross, he said no problem and switched the 90 for a 45. I'm not sure if my assembly is to "code", but it works very well.
If you have any questions, contact Ross at that link. Super nice guy.
Hope that helps
Regards,
Steve
Here's the link...https://gadgetsgo.com/2ZVWB04-Wall-Hung-4-inch-Vent-Kit-Stainless-Steel-Tankless.html
Actually it's still on sale for $169.88 free shipping ( I opted for 2-day express delivery 5.00).
The boot/wall thimble is flat, so I used a couple of 1x1 clamped in a vice and made my bents to match the contour of the corrugated steel siding on the outside. On the inside, I left the thimble flat and built a spacer out of 2x6 to protect the insulation. The wall thimble is 2 pieces that are telescopic so they fit together very tightly. Surrounded by the 2x6 "box", it forms a double walled transition thru the wall. Once together the outside dryer vent looking piece slides on and clamps. The 4"dia kit(Z-vent) is all stainless with internal gaskets on each piece. I used a little lithium grease on the gaskets for easier assembly figured it would burn off. Also wear gloves, the pieces are very sharp. The kit included a 90 degree elbow, but I needed a 45. I called and talk to Ross, he said no problem and switched the 90 for a 45. I'm not sure if my assembly is to "code", but it works very well.
If you have any questions, contact Ross at that link. Super nice guy.
Hope that helps
Regards,
Steve
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metschers
Well-known member
MrSurly,
I forgot to add, I'm using this with a Modine HotDawg 100K btu (propane).
SM
I forgot to add, I'm using this with a Modine HotDawg 100K btu (propane).
SM
bobbyjean
Well-known member
metshers-looks like a great setup...any trouble's with damper...hanging up or freezing?
metschers
Well-known member
Bobbyjean,
So far so good, I've not had any problems. I pitched the vent down slightly towards the outside and haven't had any condensation issues. I installed the heater in early November 2017. The temperature here, like the rest of the country has been from one extreme to the other. It was -2 the other night and has been in the teens thru out the week. This week is suppose to be 40-60 degrees.
The damper is actually installed right off the heater outlet so it won't freeze up.
I only use the heater when I'm working in the shop. I monitor the temperature and its never dropped below 25 dgrees (3" insulation on walls/ ceiling).
The other day it was 14 degrees outside, being a 100K heater it took about hour to bring the inside temp to 65 degrees.
Regards
So far so good, I've not had any problems. I pitched the vent down slightly towards the outside and haven't had any condensation issues. I installed the heater in early November 2017. The temperature here, like the rest of the country has been from one extreme to the other. It was -2 the other night and has been in the teens thru out the week. This week is suppose to be 40-60 degrees.
The damper is actually installed right off the heater outlet so it won't freeze up.
I only use the heater when I'm working in the shop. I monitor the temperature and its never dropped below 25 dgrees (3" insulation on walls/ ceiling).
The other day it was 14 degrees outside, being a 100K heater it took about hour to bring the inside temp to 65 degrees.
Regards
MrSurly
Well-known member
Thanks for the info, I have now ordered this set up with the 45 after speaking with Ross.
The issue tyhat I don't know the answer to right now is whether the "universal" adapter will fit to the Mr.Heater (this unit has a really *short* transition) and I'm keeping my fingers crossed.
The issue tyhat I don't know the answer to right now is whether the "universal" adapter will fit to the Mr.Heater (this unit has a really *short* transition) and I'm keeping my fingers crossed.
MrSurly
Well-known member
It 'says so'
*edit* I've not found anything that indicates a difference for water heater/furnace/space heater/boiler/spa/pool heater, whatever. Just "Fuel gas vent" class X
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My heater instructions specifically called for TEE vent.
The standard cat III tee is $50 at Menards.
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MrSurly
Well-known member
I can’t seem to find my instruction book today(!)
I do recall the drawings both showed tee style.
I don’t recall the text saying ‘must be tee’ but I don’t actually doubt it.
I had mentioned my plan to one of the city inspectors and he said they don’t have a requirement but just mfrs requirement and if I had a vent rated class iii then he was happy. But I’ll have to investigate the book again.
Also, I wonder why the tee?
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I do recall the drawings both showed tee style.
I don’t recall the text saying ‘must be tee’ but I don’t actually doubt it.
I had mentioned my plan to one of the city inspectors and he said they don’t have a requirement but just mfrs requirement and if I had a vent rated class iii then he was happy. But I’ll have to investigate the book again.
Also, I wonder why the tee?
Sent from my iPhone using Tapatalk
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dfiler2
Well-known member
Depending on where you're located you may need to use a high wind termination cap, especially if you are taking combustion air from inside.
The other call out in the instructions:
“Do not damper or add heat recovery devices to the flue piping. Failure to open such a damper prior to operating the gas unit heater will result in the spillage of flue gas into the occupied space.”
“Do not damper or add heat recovery devices to the flue piping. Failure to open such a damper prior to operating the gas unit heater will result in the spillage of flue gas into the occupied space.”