355CAV
Removal of Existing Furnaces from Common Vent Systems
When an existing Category I furnace is removed or replaced, the original venting system may no longer be sized to properly vent the remaining attached appliances. An improperly sized Category I venting system could cause the formation of condensate in the furnace and vent, leakage of condensate and combustion products, spillage of combustion products into the living space, etc.
AIR FOR COMBUSTION AND VENTILATION
!CAUTION
FURNACE RELIABILITY HAZARD
Failure to follow this caution could result in premature component failure.
This furnace can be vented as either a direct vent
Combustion-Air and Vent Pipe Systems
For additional venting information contact www.Bryant.com.
General
Vent system or vent connectors of other appliances may need to be resized. For any other appliances when resizing vent systems or vent connectors, system or connector must be sized to approach minimum size as determined using appropriate table found in the NFGC or
The 355CAV furnaces can be vented as either a direct vent furnace or as an optional ventilated combustion air application. A direct vent system shall be installed in accordance with the direct vent
Direct Vent / 2-Pipe System
In a
Ventilated Combustion Air Option Materials
In a ventilated combustion air option, the vent terminates and discharges the flue products directly to the outdoors similar to a direct vent system. See Fig. 35 for required clearances. All air for combustion is piped directly to the furnace from a space that is well ventilated with outdoor air (such as an attic or crawl space) and the space is well isolated from the living space or garage.
Materials
!WARNING
FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in personal injury, death, or property damage.
Solvent cements are combustible. Keep away from heat, sparks, and open flame. Use only in well ventilated areas. Avoid breathing in vapor or allowing contact with skin or eyes.
In Canada, construct all
!WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury, death, or property damage.
All
An abandoned masonry chimney may be used as a raceway for properly insulated and supported
A furnace shall not be connected to a chimney flue serving a separate appliance designed to burn solid fuel.
Other gas appliances with their own venting system may also use the abandoned chimney as a raceway providing it is permitted by local code, the current edition of the National Fuel Gas Code and the vent or liner manufacturer’s installation instructions. Care must be taken to prevent the exhaust gases from one appliance from contaminating the combustion air of other gas appliances. Do not take combustion air from inside the chimney when using the Ventilated Combustion Air option.
!CAUTION
UNIT MAY NOT OPERATE HAZARD
Failure to follow this caution may result in intermittent unit operation.
When vent pipe is exposed to temperatures below freezing, such as when it passes through an unheated space or when a chimney is used as a raceway, pipe must be insulated as shown in Table 6 with
Furnace combustion air and vent pipe connections are sized for 2- in. pipe. Any pipe size change should be made outside furnace casing in vertical pipe. The transition has to be made as close to the furnace as reasonably possible. (See Fig. 38.)
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