Honeywell thermostat: “Heat On” or the flame blinking
Honeywell Home gives the same answer for a blinking “Heat On” or flame as for “Cool On”: the thermostat has a built-in 5-minute delay to protect your equipment.
Applies to: Honeywell Home programmable thermostats. What you see: words and a symbol.
What Honeywell Home says to do
- Honeywell Home says to wait 5 minutes for the system to respond safely.
Same symbol, elsewhere: A flame on a boiler’s own panel shows the burner is lit.
Source
Honeywell Home’s own help page, read on the date shown.
- Honeywell Home Support: Why is the “Cool On,” “Heat On,” “Snowflake,” or “Flame” blinking on the thermostat display? — Honeywell Home programmable thermostats, filed under the Wireless 5-1-1 Day Programmable. www.honeywellhome.com Checked 2026-09-29.
A similar symbol on other thermostats
The same symbol on another maker’s thermostat can mean something else.