Venting Instructions

3
CP-UBZ-UDZ-VENT (02-21) 1034632-0
Venter Outlet and Combustion Air Inlet Connection Requirements
• Venter outlet connection on unit sizes 030, 045, and 060: when using 3-inch diameter pipe, a 4- to 3-inch (102-
to 76-mm) taper-type reducer is required at the venter outlet—for category III, attach a 4-inch appliance adapter
from a category III pipe manufacturer directly to the collar and then use a reducer if using 3-inch pipe.
• Combustion air inlet connection on unit sizes 030, 045, and 060: when using 3-inch diameter pipe, a 3- to
4-inch (76- to 102-mm) taper-type increaser is required at the inlet air collar.
• Both heater connections on unit sizes 200, 225, 250, 300, 350, and 400: require a minimum of 12 inches (305
mm) of straight pipe at both heater connections.
• Connections are shown in Figure 1. Connection sizes are listed in Table 1.
Pipe Size Requirements
• Pipe diameters of the outside (terminal) concentric pipes are listed in Table 2.
• Pipe diameter and length requirements listed in Table 3 are for the indoor sections of pipe between the heater
and the concentric adapter box.
• The minimum length between the heater and the concentric adapter box is 1 foot (305 mm) for unit sizes 030–125
and 3 feet (914 mm) for unit sizes 150–400.
Figure 1. Typical Combustion Air Inlet and Venter Outlet Connections
Table 1. Combustion Air Inlet and Venter Outlet Connection Sizes
Connection
Unit Size
030, 045, 060, 075, 100, 125 150, 175, 200, 225, 250 300, 350, 400
Connection Diameter (Inches (mm))
Venter outlet
4 (102)
5 (127)
6 (152)
Combustion air inlet collar 6 (152)
Table 2. Concentric (Outdoor) Pipe Sizes
Pipe
Unit Size
030, 045, 060, 075, 100, 125 150, 175, 200, 225, 250, 300, 350, 400
Pipe Diameter (Inches (mm))
Inlet air 6 (152) 8 (203)
Vent 4 (102) 5 (127)