Bradford White UCG100H270 Installation And Operation Manual page 17

Vertical Installation
Vertical venting system must be supported every 5 feet of vertical run and every 3 feet of horizontal run of vent pipe
length.
Failure to properly support the vent piping with hangers and clamps may result in damage to the water heater or venting
system.
WARNING! DO NOT USE 2"
VENT WITH UCG100H399
MODELS
Figure 5. Typical Vertical Intake Vent System Installation.
CAUTION
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