Weil-mclain 381-359-310 CGA-8 Cast Iron Gas Water Boiler 172000 Btu Spark Ignition Natural Gas Series 4 Replaces 381-359-082

Product Description

The Weil-McLain 381-359-310 is a CGA-8 Series 4 cast iron, gas-fired hydronic water boiler rated at 172,000 BTU output and designed for residential and light commercial heating applications. This unit runs on natural gas with spark ignition and operates without a draft hood, making it a reliable choice for forced hot water heating systems. HVAC professionals and licensed heating contractors rely on the CGa Series 4 for its combination of proven cast iron construction, service-friendly design, and strong efficiency ratings. The boiler carries an 84% AFUE rating and a DOE rating of 198,000 BTU, with a BTU input of 233,000 BTU. The IBR rating is listed at 172,000 BTU, confirming its output capacity for hydronic heating loads in a wide range of building types. The unit operates at 120 volts and includes a pressure relief setting of 30 psi, standard for residential hot water boiler systems. Gas connection is sized at 3/4 inches, and the water connection is 1-1/2 inches, fitting standard residential and light commercial piping configurations. The vent size is 7 inches, and the vent type is power vent. Physical dimensions are 64-7/8 inches in height, 25 inches in width, and 23-1/4 inches in depth. Shipping weight is 425 pounds, so freight delivery with lift gate service is recommended. Stainless steel burners deliver quieter ignition and extended service life compared to traditional burner materials. A built-in low water cut-off adds an extra layer of protection and reduces the need for additional safety components. Vertical flue ways and top-cleaning access make routine maintenance straightforward for service technicians. This boiler replaces part number 381-359-082, making it a direct drop-in upgrade for existing CGa installations. The CGa Series 4 line is available in seven sizes, ranging from 38 to 233 MBH, giving contractors flexibility across different load requirements.

• Cast iron sections provide long-term durability and heat retention in hydronic heating systems
• 84% AFUE efficiency with stainless steel burners for quieter ignition and improved combustion performance
• Built-in low water cut-off, accessible controls, and top-clean flue ways simplify installation and ongoing service

Product Highlights

The Weil-McLain 381-359-310 CGA-8 Series 4 delivers 172,000 BTU output in a rugged cast iron package with 84% AFUE efficiency, spark ignition, and service-friendly features that meet the demands of licensed HVAC and heating professionals.

Product Information

Standard Information

• Brand: WEIL-MCLAIN
• Manufacturer Part Number: 381-359-310

Technical Specifications

• BTU Output: 172,000 BTU
• BTU Input: 233,000 BTU
• IBR Rating: 172,000 BTU
• DOE Rating: 198,000 BTU
• Fuel Type: Natural Gas
• Ignition Type: Spark Ignition
• Vent Type: Power Vent
• Vent Size: 7 inches
• System Type: Hydronic (Water)
• Boiler Type: Standard
• Efficiency (AFUE): 84%
• Voltage: 120V
• Pressure Relief: 30 psi
• Gas Connection: 3/4 inches
• Water Connection: 1-1/2 inches
• Height: 64-7/8 inches
• Width: 25 inches
• Depth: 23-1/4 inches
• Weight: 425 pounds
• Warranty: 20 Year (Heat Exchanger) / 2 Year (Parts)
• Application: Heating
• Replaces: 381-359-082