CGA-3 - 48,000 BTU Output Boiler, Spark Ignition - Series 3 (Natural Gas)

Weil-McLain CGA-3 – 49,000 BTU Gas-Fired Atmospheric Cast Iron Boiler

The Weil-McLain CGA-3 is a high-efficiency, gas-fired, cast iron boiler designed for residential hot water heating applications. With a DOE heating capacity of 49,000 BTU/h and an AFUE of 84%, it delivers consistent performance in systems requiring reliability, safety, and serviceability. The CGA Series is ideal for baseboard, radiator, or radiant floor installations.

System Performance Overview

• Input: 60,000 BTU/h
• DOE Heating Capacity: 49,000 BTU/h
• Net I=B=R Rating: 43,000 BTU/h
• AFUE Efficiency: 84%
• Fuel: Natural Gas

Construction & Design Features

• Heat Exchanger: Cast iron sections with factory-tested seals
• Vent Type: Natural draft – 5” flue outlet
• Burner: Stainless steel tubular burners for clean combustion and long life
• Controls: Integrated control module with low water cutoff (LWCO) and flame rollout protection
• Serviceability: Vertical flueways and top-access panels for simplified maintenance

Boiler Configuration

• Ignition: Intermittent electronic ignition system
• Maximum Working Pressure: 50 PSI
• Dimensions: Approx. 17" W × 27" D × 30" H
• Weight: ~330 lbs
• Electrical: 120V / 60 Hz / 15A

Installation Considerations

The CGA-3 is suited for closed-loop hydronic systems in residential applications. Proper venting, combustion air supply, and gas line sizing must be verified on site. Weil-McLain provides full installation instructions with approved clearances and piping schematics. Due to combustion and venting requirements, installation should be performed by a licensed HVAC or plumbing professional in accordance with local codes.

Field Applications & Use Cases

• Space Heating Only: No integrated DHW coil – indirect water heater recommended if DHW is required
• Ideal For: Radiators, fin-tube baseboard, radiant in-floor applications
• Project Fit: Well-suited for residential boiler replacement in compact mechanical rooms or retrofits with existing natural draft venting

Built-In Safety Features

• Low water cutoff pre-installed to prevent dry fire damage
• Flame rollout switch and blocked vent switch for combustion safety
• High-limit temperature control

The Weil-McLain CGA-3 provides a field-proven, cast iron solution for reliable residential heating. With straightforward service access and robust safety features, it’s engineered to support professional-grade installations that demand both performance and dependability.