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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 381-359-304 is a CGA-25 Series 4 cast iron, gas-fired hydronic water boiler designed for residential and light commercial heating applications. This unit delivers 27,000 BTU of verified output power from a 38,000 BTU input, giving it an efficiency rating of 84 percent. It runs on natural gas and uses spark ignition for reliable, consistent startup without a standing pilot light. The boiler comes paired with a Taco 007e circulator pump, providing a ready-to-install hydronic heating solution for licensed HVAC professionals and plumbing contractors. Cast iron construction is a proven choice for long-service heating equipment. It resists corrosion, handles repeated thermal cycling, and holds heat well. The CGa Series 4 line has been a trusted name in forced hot water boiler systems for decades, commonly found in older and new residential buildings alike. This model carries an IBR rating of 28,000 BTU and a DOE heating capacity rating of 32,000 BTU. It connects to natural gas supply lines via a 1/2 inch gas connection and ties into the hydronic loop through 3/4 inch water connections. The vent configuration uses Type B venting, which means it requires a lined chimney or B-vent pipe for proper flue gas exhaust. Vent size is 4 inches. The boiler measures 45 and 3/8 inches in height, 10 inches in width, and 4 inches in depth, making it a compact footprint for mechanical room installations. Maximum rated operating altitude is 4,500 feet above sea level. The heat exchanger carries a 20-year warranty, and parts are covered for 2 years. This boiler is intended for installation, commissioning, and service by a licensed and qualified heating professional only. All warranty and technical support inquiries must be handled by the licensed contractor responsible for the installation.
The Weil-McLain 381-359-304 CGA-25 Series 4 delivers reliable 27,000 BTU hydronic heating with cast iron durability, 84 percent efficiency, and an integrated Taco 007e circulator. It is a proven solution for residential and light commercial hot water 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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