Bradford White PDX1-40S6FBN Installation And Operating Instruction Manual page 33

Venting continued-
THROUGH THE ROOF VENTING: (VERTICAL VENTING CONCENTRIC
VENT TERMINAL):
Cut the necessary holes through the roof and ceiling and install the vent
connector as shown in Figure 14. Make sure that the installation meets the
local codes and/or the National Fuel Gas Code ANSI Z223.1 (Latest Edition) or
CAN/CGA B149 installation code (latest edition). A condensate kit must be
installed when venting through the roof.
Figure 14
NOTE: For installations requiring both horizontal and vertical runs,
the following rule must be followed. Total length of straight pipe
(both horizontally and vertically) must not exceed the equivalent
length listed in these instructions. For the concentric vent terminal
the maximum vent length is reduced by 10 feet.
CAUTION
FOR VERTICAL INSTALLATIONS WITH CONCENTRIC VENT
TERMINAL, CONDENSATE KIT, P/N 239-45875-00, MUST BE USED.
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