Air Inlet Pipe Materials - Slant/Fin VGH-299-CH Installation And Service Manual

9.5.4 A
IR INLET PIPE MATERIALS
The air inlet pipe(s) must be sealed. Choose acceptable combustion air inlet pipe materials from the following list:
- PVC, CPVC or PP
- Flexible propylene air intake
- Galvanized steel vent pipe with joints and seams sealed as specified in this section.
- Type "B" double-wall vent with joints and seams sealed as specified in this section.
- AL29-4C, stainless steel material to be sealed to specification of its manufacturer.
Using air intake materials other than those specified can result in personal injury, death or
property damage.
WARNING
The use of double-wall vent or insulated material for the combustion air inlet pipe is
recommended in cold climates to prevent the condensation of airborne moisture in the incoming
combustion air.
NOTICE
Sealing of Type "B" double-wall vent material or galvanized vent pipe material used for air inlet piping on a wall or
vertical rooftop Combustion Air Supply System:
a. Seal all joints and seams of the air inlet pipe using either Aluminum Foil Duct Tape meeting UL Standard
723 or 181A-P or a high-quality UL Listed silicone sealant such as those manufactured by Dow Corning
or General Electric.
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.
The PVC or CPVC air inlet pipe must be cleaned and sealed with the pipe manufacturer's recommended solvents
and standard commercial pipe cement for the material used.
Proper sealing of the air inlet pipe ensures that combustion air will be free of contaminants and supplied in proper
volume.
Follow the polypropylene or flexible polypropylene manufacturer's instructions when using polypropylene material
as an inlet pipe.
When a wall 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.
Failure to properly seal all joints and seams as required in the air inlet piping may result in flue
gas recirculation, spillage of flue products and carbon monoxide emissions causing severe
personal injury or death.
DANGER
E93.1601EN032.C VGH installation manual 39