Crown Boiler BWF Series Installation Instructions Manual page 66

Appendix A (continued)
C. Air Intake System Assembly -
1. If PVC piping is used, use PVC cement to
assemble the PVC intake system components.
2. If metallic "smoke pipe" is used, use at least
three sheet metal screws per joint. Seal the
outside of all joints.
3. The male end of metallic "smoke pipe" will
fit inside the air inlet collar on the boiler.
Secure with a single #10 sheet metal screw
and seal the outside of the joint with silicone
sealant.
Figure A.7: Vertical Direct Vent System Using Disk Intake Terminal (Vent Options 8-10)
66
Table A.8: Equivalent Lengths for Air Intake Fittings
(See Section 6 for Vent Fitting Equivalent Lengths)
FITTING
Short Radius PVC 90° Elbow
Long Sweep/Sanitary 90° Elbow
5 Pc. Galvanized 90° Elbow
PVC or Galvanized 45° Elbow
4. If PVC is used for the intake system, the PVC
will fit over the outside of the air intake collar
on the boiler. Secure the PVC pipe directly to
the boiler using a single sheet metal screw
and seal the outside of the joint with silicone
sealant.
5. Two 90-degree elbows may be used to make
the 180-degree air intake termination elbow
used on vertical direct vent installations.
EQUIVALENT LENGTH (ft)
3" 4"
10.0 13.0
4.0 9.0
5.5 8.0
3.0 4.5
109836-01 - 04/20