Weil-McLain Ultra Series 4 155,000 BTU Condensing Gas Boiler

Weil-McLain Ultra Series 4 155,000 BTU Condensing Gas Boiler

Weil-McLain is a leading North American Brand of hydronic comfort heating systems for residential, commercial and institutional buildings, since 1881. Contractors, engineers, architects, homeowners, and facility managers alike rely on Weil-McLain boilers for their comfort heating needs. Installed in homes, offices, schools, restaurants, hotels, and other facilities throughout North America, the Weil-McLain brand is among the most trusted and often used in the building industry.

Features

• Cast aluminum coated heat exchanger
• Designed to operate in low temperature condensing applications
• Outdoor reset and domestic hot water priority
• Modulates with 5:1 turn-down ratio
• High grade stainless steel burner features quiet operation
• U-Control gives the power for easy set-up and maintenance
• Multiple set-up and zone options
• System sensing recognizes system and outdoor temperatures
• Temperature management for up to three different set-points
• Control multiple boilers from a single control panel
• Standard screen messages provide service alerts and maintenance reminders

What Our Experts Think

• High-efficiency condensing performance: The Weil-McLain Ultra Series 4 155,000 BTU Condensing Gas Boiler delivers up to ~95% AFUE, converting more fuel into usable heat and cutting energy costs compared to conventional boilers.

• Powerful heat output: With 155,000 BTU/h capacity, it’s ideal for large homes, multi-family units, or light commercial spaces needing robust, reliable hydronic heat.

• Quiet, smooth operation: Engineered for stable combustion and reduced noise, offering dependable comfort with minimal disruption.

• Durable and service-friendly: Weil-McLain’s design emphasizes long-lasting components, corrosion resistance, and accessible service points — making maintenance easier for pros.

Product Q&A

• What type of boiler is this?
  A high-efficiency condensing gas boiler that uses advanced heat-recovery technology to extract extra heat from combustion gases before venting.

• What heating systems does it support?
  Works with hydronic baseboard, radiant floor, fan-coils, and chilled-water reheat systems where hot water heating is used.

• What fuel does it use?
  Natural gas (propane conversion kits are often available separately via qualified installers).

• Does it require special venting?
  Yes — condensing boilers use low-temperature PVC/CPVC or polypropylene venting due to cool exhaust temperatures.

Maintenance Tips

• Annual HVAC inspection: Have a licensed technician service the boiler yearly — check heat exchanger, burner, controls, and combustion efficiency.

• Check condensate drain: Keep the condensate line clear and flowing to avoid buildup or freeze issues.

• Monitor system pressure: Maintain proper boiler pressure and make adjustments per the manufacturer’s guidance.

• Clean air intake & vents: Remove debris around air inlet and exhaust terminations to ensure safe combustion.

• Inspect for leaks: Periodically check around valves, pumps, and piping for water or gas leaks.

• Maintain water quality: Use proper inhibitors and periodic flushing to keep the hydronic system clean and corrosion-free.