Raypak 122-322 Operating And Installation Instructions page 32

The total length of the horizontal thru-wall exhaust vent system should not exceed seventy (70) feet in length. If horizontal
run exceeds 70 feet, an appropriately sized extractor must be used. To maintain proper operation pressure reading must be
between -.01" to -.08" W.C. as measured 12 in. from the appliance flue outlet. Each elbow used is equal to ten (10) feet of
straight pipe. This will allow installation in one of the four following combinations.
· 70' of straight flue pipe.
· 60' of straight flue pipe and one elbow.
· 50' of straight flue pipe and two elbows.
· 40' of straight pipe and three elbows.
The vent cap is not considered in the overall length of the venting system.
The vent must be installed to prevent the flue gas leakage. Care must be taken during assembly to ensure 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. The Raypak supplied flue exhaust direct vent cap must be utilized.
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 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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