Existing building retrofit

Gradient’s All-Weather 120V unit can fit windows with a minimum width of 26”. Each window heat pump unit plugs into a standard 120V outlet within 6 feet of the installation (no electrical panel upgrades), and is designed to operate in most climates, from -13°F to 115°F.

Other required installation conditions:

• Wall depth of 6.25 to 20 inches (measured from the inside window sill to the outside wall) to fit the mounting bracket.

• Stable window and surrounding structure that can safely support the unit and bracket (total weight about 140 lbs).

• Window that is at least 21 inches above the floor for safe installation.

• Clear space around the outdoor side of the unit to ensure proper airflow; avoid spots blocked by walls, plants, or furniture.

Buildings which are master-metered (where the owner pays one utility bill for the whole building) or buildings that are fully tenant metered (where each unit has its own meter). Building wide WiFi preferred but not necessary.

Minimum project size is a multifamily building (typically 5+ units).

Preferred project size is larger buildings, i.e., 10+ dwelling units; dorms; manufactured housing; ADUs etc.

Gradient reccomends that their units are connected to WiFi to ensure that their customer service team can proactively monitor and address issues if they arise. Graident also offers a building management system for its fleet of units, Nexus, which enables building owners to monitor the energy usage and performance of their fleet on the back end. Nexus will also integrate demand response capabilities this year.

In spaces without a window, building owners could consider pairing window heat pumps with packaged terminal heat pumps, although this increases the amount of construction involved.

No specialized skills or tools are required for installation. Gradient is actively developing its qualified installer network conducting trainings with contractors who would like to learn how to install and service our equipment. Gradient will also train building maintenance staff on installation procedures and routine maintenance. See Gradient's installation manual for more info.

Gradient currently works directly with building owners to retrofit central heating and cooling systems with their window heat pumps. Eventually, Gradient heat pumps will be available in more traditional direct to consumer channels (i.e. Home Depot, Lowes, Costco, etc)