WTGO-3LR - 75,000 BTU Output Cast Iron Gold Oil Boiler w/ Tankless Heater for Levittown Homes - Series 4 (Burner not included)

Weil-McLain WGO-3LR Oil-Fired Water Boiler – Model 386701028

The Weil-McLain WGO-3LR is a cast iron, oil-fired water boiler designed for residential and light commercial hot water heating systems. Built for long service life and high thermal efficiency, this model delivers 87% AFUE and is compatible with both single- and multi-zone hydronic configurations. It is ideal for applications requiring a tankless coil and is shipped with either assembled or knockdown options for site-specific flexibility.

Engineering & Design Overview

• Combustion Type: Atmospheric draft, oil-fired
• Boiler Output: 75,000 BTU/hr (Net I=B=R)
• AFUE: 87%
• Heat Exchanger: Cast iron sectional design with elastomer sealing gaskets
• Venting: Rear or top flue outlet options to accommodate varied mechanical room layouts
• Flue Connection Size: 6” diameter
• Working Pressure: 50 PSIG (tested), 30 PSIG relief valve included (ASME-certified)
• Ignition: Beckett AFG burner configured for No. 2 fuel oil

Mechanical Features

• Tankless Water Heater Coil: Integrated high-capacity tankless coil for domestic hot water supply (GPM varies by inlet temp and flow rate)
• Swing-Away Burner Door: Provides unobstructed access to combustion chamber for maintenance and inspection
• Quick-Open Top Panel: Increases visibility of internal components during servicing
• Recessed Target Wall: Shields chamber components from flue brush damage during cleaning
• Factory-Wired Junction Box: Includes circulator wiring, service switch, and safety controls pre-installed
• Circulator: Pre-installed Taco circulator (model may vary by distribution region)

Installation Notes

The WGO-3LR is available in assembled or knockdown formats, supporting basement retrofits or tight-access installations. Installation must comply with all local and national mechanical codes. A professional installer is required to ensure correct burner setup, flue configuration, circulator sizing, and tankless coil piping (if used). The boiler ships with factory pressure controls, aquastat, and ASME relief valve. Burner must be adjusted for proper draft and combustion during commissioning.

Control & Safety Components

• Honeywell L7224U digital aquastat with high limit and circulator control
• Low water cutoff option (field installed)
• Flame retention head burner (Beckett AFG standard)
• Manual reset high limit protection and blocked vent switch (as applicable by region)

Physical Dimensions & Connections

• Water Supply/Return: 1-1/4" NPT
• Tankless Coil Connection: 3/4" NPT
• Approximate Shipping Weight: 460 lbs (assembled)
• Overall Dimensions (L x W x H): ~21-3/4" x 21-3/4" x 33-1/2"

Application Summary

The Weil-McLain WGO-3LR is well-suited for residential applications requiring a durable, oil-fired water boiler with integrated domestic hot water production. It offers proven performance for retrofit and replacement jobs where cast iron reliability and simple field servicing are valued. With two flue outlet options, elastomer sealing, and a high-capacity tankless coil, the WGO-3LR meets a wide range of installation conditions with minimal additional assembly required on site.