Heat pumps for multifamily housing are catching on, though. The airHome Multi is a cold-climate heat pump with a SEER2 rating of up to 23 and an HSPF2 rating of up to 10. Midea also offers the Packaged Window Heat Pump, or PWHP, a self-contained, cold-climate heat pump similar to a window a/c unit. The PWHP was introduced in 2023 and is being deployed in more than 20,000 public housing units in New York City. Another company, Gradient, makes a similar heat pump that is also being installed in New York City public housing.