Exhaust vent Reznor Fe75

[biggeee]

I am putting in a Fe75 Rezor. Power vent exhaust. Plan is to bring the exhaust up vertically 10 ft and then thru the wall. Total of the horizontal run from the vertical is 3 ft to the cap outside. Here is the vent information from the manual.

2. Vent Pipe
If installed with a horizontal vent run, use either vent pipe ap-
proved for a Category III heater or appropriately sealed 26-gauge
galvanized steel or equivalent single-wall pipe.
If at least half of the equivalent length of the vent system is verti-
cal, vent pipe approved for a Category I heater may be used.
Single-wall pipe or double-wall (Type B) vent pipe are suitable for
use with a Category I heater.
Use only one of the flue pipe diameters listed in the Vent Length
Tables for the furnace size being installed.


So can I use B vent or must I use type iii since more than half is vertical or am I reading this wrong...Thanks

 

[Gizzi]

Venting can be pretty confusing compared to older code. The way I'm reading current requirements, the system is defined as vertical if the horizontal distance is less than 75% of the vertical distance. So if it's vertical, you can use Cat 1 B vent. If it's horizontal, you need to use Cat 3 Stainless vent (expensive!). The fact that it is power vented doesn't inherently mean the exhaust vent is at positive pressure, it just means the heat exchanger is now having draft 'induced' across it (negative pressure) as opposed to a solely atmospheric natural draft (positive pressure in heat exchanger). Even most induced 80 percent efficiency and lower still rely on natural draft in the exhaust vent to function correctly, hence most garage heaters fall under Category 1 venting.

 

[biggeee]

So if I come out of the heater vertically 12 ft and then go 3 ft horizontally out the SIDE of the garage (not the roof) to an end cap, would it be considered vertical.

 

[Gizzi]

So if I come out of the heater vertically 12 ft and then go 3 ft horizontally out the SIDE of the garage (not the roof) to an end cap, would it be considered vertical.

I've never installed a heater like that, but I would assume that so long as your vertical piping is more than 75 percent of your horizontal, then it should be considered a vertical install.

 

[biggeee]

Really hoping I can get more input before I do something on this. Please let me know your opinions