Weil-mclain 381-359-364 CGI-6 Cast Iron Hot Water Boiler 117000 Btu Output Spark Ignition Natural Gas Series 5 with Taco 007 Circulator

Product Description

The Weil-McLain 381-359-364 is the CGI-6 Series 5 cast iron gas-fired hot water boiler designed for residential and light commercial hydronic heating systems. This unit delivers 117,000 BTU of output from a 158,000 BTU input, achieving a steady 84% thermal efficiency. It runs on natural gas and uses spark ignition for reliable startup without a standing pilot light. The boiler ships with a Taco 007 circulator already included, reducing the need for additional components at installation. Cast iron sectional construction gives this boiler outstanding durability and long service life. Cast iron holds heat well and resists corrosion from hydronic system water over decades of use. The insulated steel jacket reduces standby heat loss and helps maintain system efficiency. This is a power vent boiler, meaning it uses a motorized blower to exhaust combustion gases through a 3-inch vent pipe. Power vent configurations allow greater flexibility in flue routing compared to natural draft systems, a key advantage in retrofit and replacement jobs. The CGI-6 carries an IBR rating of 117,000 BTU and a DOE heating capacity rating of 135,000 BTU, both important benchmarks that HVAC contractors and engineers reference when sizing hydronic systems. Water connections are 1-1/4 inches and the gas supply connection is 1/2 inches. Operating pressure relief is set at 30 psi. The unit operates on standard 120V power. At 19 inches wide, 23-1/4 inches deep, and 28-3/8 inches tall, this boiler fits into typical mechanical room footprints. Weil-McLain backs the heat exchanger with a 20-year warranty and covers parts for 2 years. Installation, commissioning, and service must be performed by a licensed heating professional in accordance with all applicable codes and manufacturer guidelines.

• 117,000 BTU output with 84% efficiency on natural gas fuel
• Cast iron sectional heat exchanger with insulated steel jacket for durability and heat retention
• Power vent configuration with spark ignition and included Taco 007 circulator

Product Highlights

The Weil-McLain CGI-6 Series 5 combines rugged cast iron construction with a 20-year heat exchanger warranty, making it a dependable long-term solution for residential and light commercial hydronic heating applications. The included Taco 007 circulator and power vent design simplify installation for licensed heating contractors.

Product Information

Standard Information

• Brand: WEIL-MCLAIN
• Manufacturer Part Number: 381-359-364

Technical Specifications

• Product Type: Boiler
• Boiler Type: Standard
• System Type: Hydronic (Water)
• Fuel Type: Natural Gas
• Ignition Type: Spark Ignition
• Vent Type: Power Vent
• BTU Input: 158,000 BTU
• BTU Output: 117,000 BTU
• DOE Rating: 135,000 BTU
• IBR Rating: 117,000 BTU
• Efficiency: 84%
• Voltage: 120V
• Pressure Relief: 30 psi
• Water Connection: 1-1/4 inches
• Gas Connection: 1/2 inches
• Vent Size: 3 inches
• Width: 19 inches
• Height: 28-3/8 inches
• Depth: 23-1/4 inches
• Warranty: 20 Year (Heat Exchanger) / 2 Year (Parts)
• Application: Heating