Raypak 122-322, Operating And Installation Instructions

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Horizontal Thru-wall Direct Vent System (Category III) Installation
These installations utilize the heater mounted blower to draw combustion air from outdoors and vent combustion products to
the outdoors.
The total length of the thru-wall exhaust vent cannot exceed forty (40) feet in length for the flue outlet. Each elbow used is
equal to ten (10) feet of straight pipe. This will allow installation in one of the three following combinations.
· 40’ of straight flue pipe.
· 30' of straight flue pipe and one elbow.
· 20' of straight flue pipe and two elbows.
The total length air supply pipe cannot exceed forty (40) feet in length for the combustion air inlet. Each elbow used is equal
to ten (10) feet of straight pipe. This will allow installation in one of the three following combinations.
· 40’ of straight combustion air pipe
· 30' of straight combustion air pipe and one elbow.
· 20' of straight combustion air pipe and two elbows.
The flue exhaust direct vent cap is not considered in the overall length of the venting system.
Care must be taken during assembly that all joints are sealed properly and are airtight.
The vent must be installed to prevent the potential accumulation of condensate in the vent pipes. It is recommended that:
a) The vent be installed with a slight downward slope of not more than 1/4" per foot of horizontal run to the vent terminal.
b) The vent be insulated through the length of the horizontal run.
For appliances installed in extreme cold climate, it is recommended that:
a) The vent be installed with a slight upward slope of not more than 1/4" per foot of horizontal run to the vent terminal. In
this case, an approved condensate trap must be installed per applicable codes.
b) The vent be insulated through the length of the horizontal run.
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Horizontal Thru-wall Direct Vent Termination
The flue exhaust direct vent cap MUST be mounted on the exterior of the building. The direct vent cap cannot be installed in
a well or below grade. The direct vent cap must be installed at least one (1) foot above ground level and above normal snow
levels.
Multiple direct vent caps MUST NOT be installed with one combustion air inlet directly above a direct vent cap. This vertical
spacing would allow the flue products from the direct vent cap to be pulled into the combustion air intake installed above.
This type of installation can cause non warrantable problems with components and poor operation of the unit due to the
recirculation of flue products. Multiple direct vent caps should be installed in the same horizontal plane with a three (3) foot
clearance from the side of one vent cap to the side of the adjacent vent cap(s).
Combustion air supplied from outdoors must be free of particulate and chemical contaminants. To avoid a blocked flue
condition, keep the vent cap clear of snow, ice, leaves, debris, etc.
WARNING: No substitutions of flue pipe or vent cap material are allowed. Such substitutions would jeopardize the
safety and health of inhabitants.
The Stainless Steel flue exhaust direct vent cap must be furnished by the heater manufacturer in accordance with its listing.
Use only the special gas vent pipes listed for use with category III gas burning heaters, such as the stainless steel vent by
Heat Fab Inc (800-772-0739), Protech Systems, Inc. (800-766-3473) or Z-Flex (800-654-5600). Pipe joints must be positively
sealed. Follow carefully the vent manufacturers installation instructions.
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