Is It Bad or Normal if Auxiliary Heat Comes On

Informational banner from HVAC Guidepost explaining whether it's bad or normal if auxiliary heat comes on, featuring 3D icons for auxiliary heat, a checkmark for normal operation, and an exclamation mark for potential issues, with bold teal and orange visuals on a light background.

Seeing “AUX heat” pop up on your thermostat? You’re not alone — and you’re right to ask whether it’s a red flag or just business as usual. At HVAC Guidepost, we’ve helped hundreds of homeowners make sense of auxiliary heat behavior, and here’s what we’ve seen: it’s often normal during cold snaps, especially in systems … Read more