Lennox announced that its commercial cold climate heat pump rooftop unit (RTU) is the first in the 15–25 tons category to successfully complete laboratory validation under the U.S. Department of Energy’s (DOE) Commercial Building HVAC Technology Challenge.
The company developed the system at its Texas Product Development and Research laboratory. The DOE and the National Renewable Energy Laboratory (NREL) independently validated that the RTU meets, and in many cases exceeds, the challenge’s performance requirements. The technology is designed to improve heat pump efficiency in cold climates and address defrost limitations.
According to DOE, commercial building space conditioning represents about 40% of commercial energy use in the United States. Lennox is one of eight manufacturers participating in the challenge. Later in 2025, the prototype unit will be installed in a U.S. commercial building for field validation during severe winter conditions.
"We approach advanced technology development with the intent to deliver practical, real-world solutions, and the successful validation of our rooftop cold climate heat pump brings us another step closer," said Lennox Chief Technology Officer Prakash Bedapudi. "This unit reflects years of focused research and development to overcome cold-climate limitations, particularly around defrost, and deliver consistent comfort in the toughest conditions. Our team is proud to be the first to complete the challenge while meeting the evolving needs of our customers."
The validation follows Lennox Residential HVAC’s earlier participation in the DOE Residential HVAC Challenge, where the company was the first to complete Phase 1 testing in 2022.