WGO-3R - 85,000 BTU Output Cast Iron Gold Oil Boiler - Series 4 (Burner is not included)

Weil-McLain WGO-3R – Oil-Fired Water Boiler, High-Efficiency, Cast Iron

The Weil-McLain WGO-3R is a water-only oil-fired boiler built for residential and light commercial hydronic heating systems. Manufactured with cast iron heat exchanger sections and designed for long service life, this model offers dependable operation and flexible installation options.

This model is engineered with a quick-open top and swing-out burner door for full chamber access, simplifying inspection and maintenance tasks. The WGO-3R is equipped with a recessed target wall for added protection from cleaning equipment, and the insulated steel jacket minimizes standby losses.

Product Highlights

• Heat Output: 85,000 BTU/hr (DOE)
• AFUE Efficiency: 87%
• Flue Options: Top and rear outlet flue connections
• Circulator: Factory-installed, pre-wired circulator with integral service switch
• Combustion Chamber: Access via swing-away burner door for simplified service
• Burner: Not included (compatible with standard Beckett, Carlin, or Riello oil burners)

Construction & Materials

• Heat Exchanger: Cast iron sectional
• Jacket: Insulated steel casing to reduce thermal loss
• Target Wall: Recessed, non-metallic, brush-resistant target wall
• Working Pressure: 50 PSI
• Warranty: 20-year limited warranty on the heat exchanger; 2 years on parts

Application & Installation

• System Type: Closed-loop hydronic heating, water-only (no tankless coil)
• Mounting: Floor-standing unit, shipped assembled
• Fuel: #2 heating oil
• Venting: Natural draft; requires appropriate chimney connection
• Circulator Location: Left side standard; connections designed for easy access

Installation Guidelines

Professional installation is strongly recommended to ensure compliance with regional fuel codes and system requirements. Installer must provide burner selection, fuel line setup, and proper flue configuration based on available venting path and draft conditions. Electrical wiring is simplified with factory-mounted circulator and service switch. Proper combustion air supply and clearance allowances should be confirmed prior to placement.

Notes for Field Technicians

• Boiler ships as water-only configuration with no tankless coil opening
• Chamber access is tool-free; suitable for annual brushing and inspection
• Factory-tested to meet DOE compliance; verify nozzle spec when selecting burner
• Recommended for zone systems using standard circulators or zone valves