CGA-7 - 147,000 BTU Output Boiler, Spark Ignition - Series 3 (Natural Gas)

Weil-McLain CGA-7 Gas Boiler – Cast Iron, Atmospheric, Residential/Light Commercial Heat Source

The Weil-McLain CGA-7 is a cast iron, gas-fired, atmospheric boiler designed to provide dependable hydronic heat output for residential and light commercial systems. With an input of 175,000 BTU/hr and a DOE heating capacity of 147,000 BTU/hr, this unit is suited for medium to large hydronic heating loads in single or multi-zone systems.

The CGA Series is engineered for durability and operational reliability, with key safety features such as a factory-installed low water cutoff and integrated draft hood. This non-condensing boiler maintains an 84% AFUE and is constructed to support decades of consistent performance with proper maintenance.

System Benefits and Technical Advantages

• Cast Iron Heat Exchanger: Durable sectional design supports high-mass water volume and even heat distribution, ideal for older radiator systems or applications with larger thermal inertia.
• Standard Atmospheric Venting: Designed for Category I venting via chimney or vertical flue. No need for power venting components.
• Burner Configuration: Intermittent electronic ignition with multiple in-shot burners provides stable combustion and quiet operation.
• Low Water Cutoff: Built-in Safeguard 100 ensures automatic shutdown if water level falls below safe operating range.
• Service Access: Easy front-panel access to gas train, controls, and burner tray simplifies routine service tasks.

Performance Specifications

• Model: CGA-7 (381359080)
• Input: 175,000 BTU/hr
• DOE Heating Capacity: 147,000 BTU/hr
• Net I=B=R Rating: 128,000 BTU/hr
• AFUE: 84%
• Fuel: Natural Gas
• Ignition: Electronic, intermittent pilot
• Vent Type: Atmospheric – chimney vent required
• Water Connections: 1-1/4" NPT
• Gas Connection: 1/2" NPT

Installation Considerations

The CGA-7 is intended for installation in systems requiring conventional venting and can be used in both new construction and replacement scenarios. The boiler’s dimensions and standard connections allow for straightforward replacement of legacy cast iron boilers.

Installation should be performed by a licensed contractor in accordance with local codes and manufacturer instructions. Proper flue sizing, combustion air supply, and system balancing are essential for safe and efficient operation.

Compliance and Standards

• CSA Certified for residential use
• Meets ASME Section IV pressure vessel code
• Input ratings compliant with DOE and AHRI standards
• Maximum Working Pressure: 50 PSI

Summary

The Weil-McLain CGA-7 boiler provides a reliable solution for hydronic heat delivery in atmospheric, non-condensing applications. Its cast iron design, integrated safety features, and 84% AFUE rating make it a solid choice for professional contractors working on retrofit or standard boiler projects. With 175 MBH input and proven field performance, the CGA-7 is engineered to meet high-output heating demands with minimal complexity and long service life.