EcoTec 150-H 150 Input MBtu 95.1% AFUE Natural Gas Condensing Heat Only Water Boiler Series 2

Weil-McLain ECO® Tec 150 – High-Efficiency Condensing Gas Boiler

The ECO® Tec 150 (Model 383900178) is a high-efficiency, wall-hung condensing boiler designed for residential heat-only applications. With a 95.1% AFUE and 150 MBH input, it delivers reliable hydronic heating performance while meeting modern energy efficiency standards. This model is suitable for both new installations and replacement projects requiring compact footprint and quiet operation.

Core System Features

• AFUE: 95.1%
• Input Capacity: 150,000 BTU/hr
• DOE Heating Capacity: 139,000 BTU/hr
• Net I=B=R Rating: 121,000 BTU/hr
• Heat Exchanger: 316L stainless steel firetube
• Control Interface: Integrated color touchscreen with guided setup, diagnostics, and zone control capabilities

Design and Performance Highlights

• Modulation Ratio: 10:1 turndown enables precise load matching and reduced short cycling
• Venting: Approved for PVC, CPVC, polypropylene, or stainless steel venting; direct or concentric configuration
• Combustion System: Factory-set for natural gas with field conversion kit for LP
• Noise Level: Quiet operation under full and partial load; suitable for utility rooms, closets, or basement installs
• Zone Control: Supports integration with up to 4 circulators or 8 zone valves

Dimensions and Connections

• Unit Dimensions (HxWxD): 35.6" × 17.5" × 17.5"
• Water In/Out: 1"
• Gas Connection: 3/4"
• Venting Diameter: 2" or 3" depending on run length and material
• Weight: Approx. 150 lbs

Installation Requirements

Professional installation is required for proper venting, gas piping, condensate management, and control setup. Combustion air and vent lengths must be calculated per the manufacturer's chart. The boiler includes a mounting bracket, pressure relief valve, condensate trap, and all necessary sensors pre-installed. Commissioning includes vent pressure verification, gas valve calibration, and enabling of zone controls if used.

Application Use Cases

Ideal for high-efficiency baseboard, panel radiator, or radiant floor systems in homes up to 4,000 sq. ft. May be integrated into multi-zone hydronic layouts and paired with indirect water heaters via the included domestic priority control logic.

Certifications

• ENERGY STAR® Certified
• ASME Section IV-stamped heat exchanger
• AHRI Certified
• CSA listed for U.S. and Canada