Reznor 53330 Combustion Air Inlet Assembly for Vertical Vent Systems

The Reznor 53330 Combustion Air Inlet Assembly is a factory-approved component designed for vertical vent/combustion air terminal installations on Reznor UDAS, UDBS, and SCE series separated combustion unit heaters. This inlet assembly is part of the complete vertical vent kit (Option CC2) and plays a critical role in delivering outside air for combustion while allowing exhaust gases to vent safely through a concentric pipe configuration.

Key Features:

• Designed for vertical roof-mount venting applications requiring only one building penetration
• Compatible with UDAS unit heaters ranging from 30,000 to 400,000 BTU input (all sizes 030-400)
• Slides over vent pipe and fastens to combustion air pipe with sheet metal screws
• Works with concentric adapter box system to separate combustion air intake from exhaust vent
• Requires high-temperature silicone sealant (included in complete kit) for proper sealing between vent pipe and inlet
• Constructed for durability in commercial, industrial, and residential garage/workshop applications

This combustion air inlet assembly is an essential component of Reznor's separated combustion system technology, which draws combustion air from outside the building rather than from the conditioned space. The separated combustion design helps prevent negative pressure issues and reduces the buildup of contaminants on the burner system. When installed as part of the vertical vent kit, the 53330 inlet assembly must extend at least 3 inches beyond the top of the vent pipe and comply with local snow depth requirements (minimum 6 inches above anticipated snow depth).

Installation Note: This component is typically included as part of the complete vertical vent kit (P/N 205895 for sizes 030-125 or P/N 205896 for sizes 150-400) and requires professional installation following Reznor's venting requirements for separated combustion units. Two inlet assemblies are included in each complete vertical vent kit.