A relatively new class of inverter driven mini-split heat pump or ductless heat pumps (DHPs) are capable of providing comfortable heating for a home when outdoor temperatures are as low as -15°F. These units are well suited for cold climates with little or no need for supplemental or backup heating. This document provides learning gathered from HVAC and building science professionals regarding optimizing performance and comfort when installing mini-split heat pump systems (DHPs, low-head “short ducted” and multi-head) in climates where winter temperatures commonly drop below 20 degrees Fahrenheit.
In addition, this document provides guidance how to get the best performance and longevity out of a cold climate DHP. It also includes discussion of unique design considerations for multi-level homes, very low load homes, and air distribution in rooms without a heat source.