Has anyone used the double wall UL 1738 compliant vent pipe when installing a Reznor UDAP garage heater? The double wall stuff is insanely expensive. The way I read the Reznor vent instructions, you are supposed to use it for residential applications even if it’s all vertical. The manual states you can use double wall B-vent pipe if it’s a commercial install and 75% of the run is vertical. Not sure why it’s acceptable for commercial, but not residential.
I looked at the manual for the Modine Hot Dawg which is very similar to the Reznor UDAP line. The both are power vented. Same BTU. Vent connection is from the side of the unit. There manual says you can use B-Vent as long as the run is 75% vertical. There is no distinction for residential or commercial. Not sure why it’s OK to use B-vent for Modine, but not Reznor. The only thing I can think of is that Reznor specially states their heater is CAT 3. The Modine manual has references to CAT 1 & 3, but it doesn’t state which category their device falls into. They make it sound like the type of installation (horizontal/vertical) dictates the category and hence the type of vent pipe required.
I’m looking to have a Reznor UDAP-60 heater installed in three car my garage. I have drywall ceiling with open attic above before the roof. There would be about 8ft of pipe in the attic, about a 2 ft in the garage space and probably another 4 feet outside to clear the roof line…so about 14 ft total. This would be a straight vertical install except for the 90 degree elbow at the unit. Based on the pricing I found, I’d be well over $1,500 just for the pipe and accessories. That’s insane!
I have a couple of contractors coming out to bid on the job and will certainly ask them. I also plan on trying to get a straight answer out of my local building inspector. While I wait, can anybody chime in on this? Did you really have to use the double wall UL 1738 pipe? I don’t want to burn my house down or cause other issues, so I will if I have to. Just want to get your thoughts on the matter.
I looked at the manual for the Modine Hot Dawg which is very similar to the Reznor UDAP line. The both are power vented. Same BTU. Vent connection is from the side of the unit. There manual says you can use B-Vent as long as the run is 75% vertical. There is no distinction for residential or commercial. Not sure why it’s OK to use B-vent for Modine, but not Reznor. The only thing I can think of is that Reznor specially states their heater is CAT 3. The Modine manual has references to CAT 1 & 3, but it doesn’t state which category their device falls into. They make it sound like the type of installation (horizontal/vertical) dictates the category and hence the type of vent pipe required.
I’m looking to have a Reznor UDAP-60 heater installed in three car my garage. I have drywall ceiling with open attic above before the roof. There would be about 8ft of pipe in the attic, about a 2 ft in the garage space and probably another 4 feet outside to clear the roof line…so about 14 ft total. This would be a straight vertical install except for the 90 degree elbow at the unit. Based on the pricing I found, I’d be well over $1,500 just for the pipe and accessories. That’s insane!
I have a couple of contractors coming out to bid on the job and will certainly ask them. I also plan on trying to get a straight answer out of my local building inspector. While I wait, can anybody chime in on this? Did you really have to use the double wall UL 1738 pipe? I don’t want to burn my house down or cause other issues, so I will if I have to. Just want to get your thoughts on the matter.