Installation & Operation Manual
4Sidewall direct venting
Prepare wall penetrations (Alternate - Field Supplied Option)
1.Air pipe penetration:
a.Cut a hole for the air pipe. Size the air pipe hole as close as desired to the air pipe outside diameter.
2.Vent pipe penetration:
a.Cut a hole for the vent pipe. For either combustible or noncombustible construction, size the vent pipe hole with at least a 1/2 inch clearance around the vent pipe outer diameter:
•5½ inch hole (140 mm) hole for 4 inch (102 mm) vent pipe
•7½ inch hole (191 mm) hole for 6 inch (152 mm) vent pipe
b.Insert a galvanized metal thimble in the vent pipe hole as shown in FIG.
3.Use a sidewall termination plate as a template for correct location of hole centers.
4.Follow all local codes for isolation of vent pipe when passing through floors or walls.
5.Seal exterior openings thoroughly with exterior caulk.
Figure 4-5B A Typical Sidewall Termination Assembly - Models 399 - 800 PVC/CPVC or Stainless Steel
Multiple vent/air terminations
1.When terminating multiple Knight XL’s terminate each vent/air connection as described in this manual (FIG.
WARNING All vent pipes and air inlets must terminate at the same height to avoid
possibility of severe personal injury, death, or substantial property damage.
2.Place wall penetrations to obtain minimum clearance of 12 inches (305 mm) between vent pipe and adjacent air inlet elbow, as shown in FIG.
3.The air inlet of a Knight XL is part of a direct vent connection. It is not classified as a forced air intake with regard to spacing from adjacent boiler vents.
Figure 4-6A Multiple Vent Terminations (must also comply with Figure 4-1A)
12" MIN. BETWEEN EDGE OF AIR 
INLET AND ADJACENT VENT OUTLET
VENT
SIDEWALL
TERMINATION PLATE
VENT
PIPING
BIRD SCREEN
ELBOW 
BIRD SCREEN
GALVANIZED
THIMBLE (WHEN REQUIRED BY LOCAL CODES)
ELBOW
AIR PIPING
AIR
VENT / AIR
TERMINATION
Termination and fittings
1.Prepare the vent termination elbow and the air termination elbow (FIG.
2.When completed, the air termination coupling must be oriented at least 12 inches (305 mm) below the vent termination and at least 12 inches (305 mm) above grade or snow line as shown in FIG.
3.Maintain the required dimensions of the finished termination piping as shown in FIG.
4.Do not extend exposed vent pipe outside of building more than shown in this document. Condensate could freeze and block vent pipe.
5.PVC/CPVC terminations are designed to accommodate any wall thickness of standard constructions per the directions found in this manual.
6.Stainless steel terminations are designed to penetrate walls with a thickness up to 9.25 inches of standard construction.
26 
Figure 4-6B Alternate Multiple Vent Terminations w/Field Supplied Fittings (must also comply with Figure 4-1B)
VENT
12” (305 MM) MIN 15” (381 MM) MAX
12” (305 MM) MIN. BETWEEN EDGE OF AIR PIPE AND ADJACENT VENT PIPE
AIR
