Lennox Allied Air A95UH1D User Manual

507270-03 Page 35 of 60Issue 1917
Exhaust through Crawl Space Vent Option
All 33” condensing gas furnaces (92%+) are now approved
to be vented down through a crawl space. Ensure a vent
pipe drain kit, 51W18 (USA) or 15Z70 (Canada), is used as
directed through the oor joists and into the crawl space.
See the following gures.
Consult the vent tables for vent lengths and approved
materials.
2” or 3”
Sanitary Tee
1/2” PVC
Drain Stub
Drain Trap
Assembly
Rubber Boot (51W18)
Drain Plug (15Z70)
Clamp
(51W18 Only)
From
Furnace
To Vent
Termination
Drain Trap
(assembled)
Figure 49. Kit 51W18 (USA) / 15Z70 (Canada) Parts
Identication and Assembly
Exhaust from
Furnace
To Termination
Exhaust from
Furnace
To Termination
* Kit 51W18 is shown.
Figure 50. Crawl Space Vent Pipe Drain Trap
Assembled Incorrectly
Figure 51. Upow or Downow Furnace with Exhaust through Crawl Space
KIT 51W18 (USA)
Basement Floor
To Te rmination
1/2” PVC to
Code-Approved
Drain
24” max.
Downflow Furnace
Exhaust
KIT 15Z70 (Canada)
* Kit 51W18 is shown.
NOTE: Upow furnaces exhaust from the left side. All dimensions shown are typical for upow or downow furnaces.
NOTE: All horizontal runs of exhaust pipe must slope back toward the kit a minimum of 1/4” (6mm) for each 12” (305mm) to ensure drainage.

Lennox Allied Air A95UH1D Specifications

General

Brand	Lennox
Model	Allied Air A95UH1D
Category	Furnace
Language	English