Allied Furnace: Venting configuration (direct vent or non-direct vent)
Venting configuration (direct vent or non-direct vent) on a Allied furnace: The furnace can go in as a Direct Vent or a Non-Direct Vent unit, and the choice changes where the combustion air comes from. With Direct Vent the air is drawn from outdoors through its own pipe. With Non-Direct Vent the furnace takes air from the room, so the space has to have enough of it. Either way, the flue gases leave the house through the exhaust pipe. Figure 2 in the manual shows roof termination layouts, so decide before you start cutting pipe.
Applies to: A95UH, A93UH, 95G1UH and 92G1UH
Common causes of venting configuration (direct vent or non-direct vent)
- Tight house or finished basement with limited indoor air, which favors Direct Vent
- Corrosive vapours, dust or chemicals indoors that make indoor air a poor choice
- Existing vent layout that decides which option fits
- Code requirements for combustion air in the mechanical room
How to fix venting configuration (direct vent or non-direct vent): step by step
- Choose Direct Vent or Non-Direct Vent before installing, because the piping differs.
- For Direct Vent, bring combustion air from outdoors through the intake pipe.
- For Non-Direct Vent, supply combustion air from indoors per the National Fuel Gas Code or CSA-B149.
- Use Figure 2 for roof termination layouts.
- After install, run a full heating cycle and look for flue gas leaks at every joint.
- Make sure intake and exhaust terminations are clear of snow, leaves and obstructions.
If the unit shows an error code, look it up: Allied Furnace codes
Models
92G1UH92G1UH0450892G1UH0451292G1UH0700892G1UH0701292G1UH0901292G1UH0901692G1UH1101692G1UH1102092G1UH1352095G1UHA93UHA95UH
Source: Allied 92G1UH installation manual, p. 8. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.