Definition
Emergency heat is a manually selected thermostat setting on heat pump systems that shuts off the outdoor heat pump and heats the home with backup heat only, usually electric resistance strips or, in dual-fuel systems, a gas furnace. Unlike auxiliary heat, which engages automatically, emergency heat is meant for a failed or damaged heat pump.
Also called: EM heat
Why it matters to you
If an outdoor unit is damaged by a falling limb or buried in ice during a winter storm, EM heat can keep a SW Washington home warm until it is repaired. On an all-electric system it runs entirely on resistance heat, so leaving it on for weeks uses far more electricity than normal operation.
Practical guidance
Switch to EM heat only when the outdoor unit is clearly not working or physically damaged, then schedule a repair rather than living on it. Diagnosing why the heat pump failed, including electrical and refrigerant checks, is licensed-technician work.
About this definition
Written by the Home Energy Group team — a family-owned HVAC company celebrating 25 years of comfort & care across SW Washington and the Portland metro, licensed in Washington (WA LIC# HOMEEGI003J7) and Oregon (OR CCB# 184255). Definitions inform; an on-site diagnosis decides.
