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This product weighs 180 lb each and will be shipped via LTL carrier. A lift gate option will be added free of charge for your convenience.
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The Weil-McLain 381-359-309 is the CGA-7 Series 4 cast iron gas-fired hydronic water boiler rated at 147,000 BTU output, designed for residential and light commercial heating applications. This boiler is part of the well-established CGa Series 4 lineup from Weil-McLain, a brand long trusted by HVAC professionals for durable, high-performance heating equipment. The CGA-7 model uses spark ignition for reliable startup and runs on natural gas, making it a practical choice for installations where dependable heating performance is a priority. It delivers 147,000 BTU of output from a 200,000 BTU input, achieving an 84 percent efficiency rating that meets the demands of modern hydronic heating systems. The IBR rating of 148,000 BTU and a DOE rating of 170,000 BTU further confirm the heating capacity of this unit for properly sized hydronic systems. The cast iron heat exchanger carries a 20-year warranty, while parts are covered for 2 years, reflecting the long service life expected from cast iron boiler construction. This unit supports both power vent and Type B chimney vent configurations, giving installers flexibility depending on the structure and existing flue setup. The boiler ships as a complete package including a Taco 007 circulator, reducing the need for additional components at the time of installation. Water connections measure 1-1/4 inches and the gas connection is 3/4 inches, fitting standard residential and light commercial piping configurations. The unit stands 62-1/8 inches tall, measures 22 inches wide, and has a 7-inch depth, with a 7-inch vent size. This boiler is intended for installation, commissioning, and service by a licensed HVAC professional in accordance with manufacturer instructions, local codes, and applicable industry standards. It is not intended for homeowner installation or service.
The Weil-McLain 381-359-309 CGA-7 Series 4 delivers 147,000 BTU output with 84 percent efficiency and spark ignition, backed by a cast iron heat exchanger built for long-term reliability in residential and light commercial hydronic heating systems.
We pulled together the parts most installs need for this unit, plus a few add-ons worth a look. Check what you need — nothing here blocks checkout.
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