Installation & Operation Manual
2 General venting (continued)
Install vent and combustion air piping
DANGER | The Crest must be vented and supplied |
with combustion and ventilation air as | |
| described in this section. Ensure the vent |
| and air piping and the combustion air |
| supply comply with these instructions |
| regarding vent system, air system, and |
| combustion air quality. See also Section |
| 1 of this manual. |
| Inspect finished vent and air piping |
| thoroughly to ensure all are airtight and |
| comply with the instructions provided |
| and with all requirements of applicable |
| codes. |
| Failure to provide a properly installed |
| vent and air system will cause severe |
| personal injury or death. |
Air inlet pipe materials:
The air inlet pipe(s) must be sealed. Choose acceptable combustion air inlet pipe materials from the following list:
ABS, PVC, or CPVC
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.
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 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, 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 ABS, PVC, CPVC, 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.
WARNING Using vent or air intake materials other than those specified, failure to properly
seal all seams and joints or failure to follow vent pipe manufacturer’s instructions can result in personal injury, death or property damage. Mixing of venting materials will void the warranty and certification of the appliance.
NOTICE | The use of | |
material for the combustion air inlet | ||
| ||
| pipe is recommended in cold climates | |
| to prevent the condensation of airborne | |
| moisture in the incoming combustion air. |
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