Authentic Hart Cooley 10rwt B Vent Round Wall Thimble 10 Inches

The HART COOLEY 10rwt is a round B vent wall thimble designed to provide a safe, fire-rated passage for Type B gas vent pipe through a combustible wall assembly. It creates the required clearance between the vent pipe and surrounding wall materials, reducing fire risk and maintaining code-compliant installation. Sized for 10-inch B vent pipe, it also accommodates 8-inch all-fuel vent systems where applicable. Licensed HVAC technicians and mechanical contractors typically install this component during new construction and vent system retrofits on gas-fired appliances.

This wall thimble is suited for residential and light commercial applications where a Type B double-wall vent must penetrate an exterior or interior combustible wall. It is appropriate for use with natural gas and propane appliances such as furnaces, boilers, and water heaters vented with Type B pipe. The 10rwt fits 10-inch B vent and is also compatible with 8-inch all-fuel vent configurations, providing flexibility across multiple vent system types on a single job.

Key Features

• Designed for 10-inch Type B double-wall gas vent pipe
• Also fits 8-inch all-fuel vent systems
• Round profile matches standard B vent pipe geometry
• Maintains required clearance to combustibles through wall assemblies
• Weighs 4 pounds — manageable for single-technician installation

Compatibility

Compatible with 10-inch Type B double-wall gas vent pipe and also fits 8-inch all-fuel vent systems, as stated by the manufacturer.

Installation Notes

Installation of this wall thimble should be performed by a licensed HVAC technician or mechanical contractor in accordance with NFPA 54 and local mechanical codes. Shut down and allow the appliance and any existing vent pipe to cool completely before beginning work. The thimble must be installed so that all clearance-to-combustibles requirements specified in the vent pipe manufacturer instructions and applicable codes are met. Do not compress, cut, or modify the thimble body in ways that reduce the designed clearance gap.

Technical Specifications

• Vent Size: 10 inches
• Wall Size: 8 inches
• Item Weight: 4 pounds

Standard Information

• Brand: HART COOLEY
• Manufacturer Part Number: 10rwt