Gradient is adding building management software to its window heat pumps, targeting the messy reality of retrofitting old apartment buildings.
The company's new Nexus platform connects individual units across an entire property, giving managers centralized control without eliminating tenant comfort. In one deployment, a building manager set heating limits at 78°F and saw energy consumption drop 25% the next day, according to Vince Romanin, Gradient's CTO.
The pitch is specific: old multifamily buildings with dying boilers and single electric meters. These properties face expensive electrical panel upgrades if they go with traditional heat pump retrofits. Gradient's units run on standard 120V outlets and install in 30-60 minutes per apartment, avoiding the panel replacement question entirely.
That matters in markets like New York, where aging steam heating systems are reaching end of life across thousands of rent-stabilized buildings. The alternative, mini-split systems, costs 70% more according to Gradient, and requires refrigerant lines, permits, and electrical work that can drag installation timelines into weeks.
Gradient has deployed units with New York City Housing Authority, Boston Housing Authority, and affordable housing in California. The company committed to 10,000 units over five years with HUD and utility partners. It's also pitching universities with older dorms built before reliable air conditioning became standard.
The software adds grid-responsive controls, potentially letting utilities manage demand across buildings during peak events. That's the kind of flexibility regulators like, but deployment data is still thin.
Notably, Gradient only sells to building owners in bulk, not direct to consumers. Competitors including Midea and Ephoca are developing similar window and through-wall units, though the market remains B2B focused.
The model uses R-32 refrigerant with one-third the global warming potential of standard R-410A. Gradient claims 95% emission reductions versus conventional HVAC in its deployments, though those figures depend heavily on grid mix.
The real test: whether building economics pencil out when boiler replacements come due. If panel upgrades cost $15,000-$30,000 per building and add months to timelines, Gradient's approach starts looking practical rather than novel.