As the demand for energy-efficient, all-electric buildings continues to grow, innovative technologies are making it easier than ever to replace traditional heating and cooling systems. At Power Path Logistics, we’re excited to offer the Gradient All-Weather 120V™ Window Heat Pump—a breakthrough solution designed specifically for existing multifamily buildings where traditional heat pump installations can be costly and disruptive.
A New Approach to Heating and Cooling
Unlike conventional window air conditioners or mini-split systems, Gradient’s unique “saddle” design sits below the window, preserving natural light, outdoor views, and the ability to open and close the window. The result is a sleek, space-saving system that delivers year-round comfort without sacrificing functionality. Inside, the Gradient heat pump utilizes the same advanced technology found in premium HVAC systems, including:
- Variable-speed inverter compressor
- Variable-speed fans
- Large, high-efficiency heat exchangers
- Factory-sealed R-32 refrigerant system
Together, these features provide exceptional heating and cooling performance while using significantly less energy than traditional systems.
Designed for Simple Installation
One of Gradient’s biggest advantages is how quickly it can be installed. The All-Weather 120V™ Window Heat Pump installs through an existing window using a no-drill mounting bracket, with installations typically completed in about 30 minutes. Because it plugs into a standard 120-volt outlet, many buildings can electrify individual apartments without expensive electrical panel upgrades or major renovations. Additional installation benefits include:
- No drilling or structural modifications
- No refrigerant piping or field charging
- No condensate drain lines thanks to patented water atomization technology
- Weather-tight insulated window panels
- Minimal disruption for residents
For building owners and property managers, that means faster projects, lower installation costs, and happier occupants.
Built for Existing Multifamily Buildings
Many older apartment buildings face significant challenges when transitioning away from fossil fuel heating. Traditional heat pump systems often require extensive electrical upgrades, refrigerant piping, ductwork, or tenant relocation during construction. Gradient was designed to solve those challenges. Originally developed through the New York City Housing Authority’s Clean Heat for All Challenge, the system provides a practical path toward electrification while avoiding many of the barriers associated with conventional HVAC retrofits.
Proven Performance in Real-World Conditions
Innovation is exciting—but proven results matter even more. During pilot installations in occupied public housing apartments, Gradient units served as the sole source of heating and cooling. The results demonstrated:
- 85–88% reductions in heating energy use
- Comfortable indoor temperatures throughout winter, including sub-freezing conditions
- High resident satisfaction, with all surveyed occupants reporting they were satisfied with or neutral toward the system’s performance
- Effective heating throughout entire apartments, not just the room where the unit was installed
These results demonstrate that window heat pumps can deliver reliable comfort while helping buildings significantly reduce energy consumption.
Ready for Large-Scale Deployment
Gradient has also proven its value on a much larger scale. At Carroll Tower, a 194-unit public housing community in Providence, Rhode Island, crews installed 277 Gradient heat pumps in just 12 days. Because the units required no ductwork, refrigerant piping, or major electrical upgrades, the retrofit was completed with minimal disruption to residents.
The project is expected to:
- Reduce annual energy consumption by approximately 450,000 kWh
- Save nearly $95,000 in annual energy costs
- Reduce greenhouse gas emissions by approximately 219 metric tons of CO₂ equivalent each year
It’s an excellent example of how innovative technology can simplify electrification while delivering measurable operational savings.
Why Power Path Logistics?
Power Path Logistics is proud to supply innovative energy-efficiency products that help utilities, program implementers, contractors, and property owners achieve their sustainability goals. The Gradient All-Weather 120V™ Window Heat Pump is another example of the forward-thinking technologies we’re bringing to market—solutions that are easier to install, reduce energy costs, improve occupant comfort, and support the transition to cleaner buildings. Whether you’re planning a multifamily retrofit, implementing an energy efficiency program, or looking for innovative products to support your customers, our team is here to help. Interested in learning more about Gradient or adding it to your next project? Contact Power Path Logistics (info@pplgx.com) to see how this innovative heat pump can fit into your energy efficiency program.