Honeywell Thermostat Heat on Blinking

Honeywell thermostats blink Heat On as a normal delay (about five minutes) to prevent short cycling; the light should stop blinking once the delay ends and heating starts. Continuous blinking beyond the delay can indicate issues like control board faults, pressure switch problems, clogged filters, power outages, mode switching, battery replacement, or low batteries. Troubleshooting steps include waiting for the delay, checking settings, resetting the thermostat, replacing batteries, inspecting breakers and HVAC components, and contacting professional or Honeywell support if the problem persists.