The Ultra® Series 4 features a state-of-the-art heat exchanger with nanotechnology coating that works like “Ultra Armor”, reducing buildup in the heat exchanger while maintaining high efficiency.
FEATURES:
- Durable Design: Cast aluminum coated heat exchanger and high-grade stainless steel burner for quiet, reliable operation.
- High Efficiency: Up to 94% DOE AFUE efficiency.
- Extended Warranty: 5-year extended warranty on service parts with boiler registration (within 90 days of installation, residential only).
- System Sensing: Monitors boiler, system, and outdoor temperatures.
- Multiple Boilers: Can control additional boilers or heating appliances.
- Temperature Management: Supports 1 to 3 setpoints for single- or multi-zone management.