3 General venting (continued)
Materials
Air inlet pipe materials:
The air inlet pipe(s) must be sealed. Choose acceptable combustion air inlet pipe materials from the following list:
PVC, CPVC, Polypropylene or ABS
Dryer Vent or Sealed Flexible Duct (not recommended for rooftop air inlet)
Galvanized steel vent pipe with joints and seams sealed as specified in this section.
Type “B”
*Plastic pipe may require an adapter (not provided) to transition between the air inlet connection on the appliance and the plastic air inlet pipe.
Installation & Operation Manual
The PVC, CPVC, or ABS air inlet pipe should be cleaned and sealed with the pipe manufacturer’s recommended solvents and standard commercial pipe cement for the material used. The PVC, CPVC, ABS, Dryer Vent or Flex Duct air inlet pipe should use a silicone sealant to ensure a proper seal at the appliance connection and the air inlet cap connection. Dryer vent or flex duct should use a screw type clamp to seal the vent to the appliance air inlet and the air inlet cap. Proper sealing of the air inlet pipe ensures that combustion air will be free of contaminants and supplied in proper volume.
When a sidewall or vertical rooftop combustion air supply system is disconnected for any reason, the air inlet pipe must be resealed to ensure that combustion air will be free of contaminants and supplied in proper volume.
DANGER | Failure to properly seal all joints and seams |
as required in the air inlet piping may | |
| result in flue gas recirculation, spillage |
WARNING
NOTICE
Using air intake materials other than those specified can result in personal injury, death or property damage.
The use of
of flue products and carbon monoxide |
emissions causing severe personal injury |
or death. |
Sealing of Type “B”
a.Seal all joints and seams of the air inlet pipe using either Aluminum Foil Duct Tape meeting UL Standard 723 or
b.Do not install seams of vent pipe on the bottom of horizontal runs.
c.Secure all joints with a minimum of three (3) sheet metal screws or pop rivets. Apply Aluminum Foil Duct Tape or silicone sealant to all screws or rivets installed in the vent pipe.
d.Ensure that the air inlet pipes are properly supported.
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