There are several issues that could prevent your thermostat from turning on your ac, these include:

Honeywell thermostat snowflake. If your thermostat is showing a blinking snowflake icon don’t panic, there’s nothing wrong with your system. My honeywell programmable 8120 thermostat has a red blinking snowflake on top right corner. A number of models have a (anti) frost mode.

I turn the thermostat off, recycle all switches and when it turns on. Verify that the thermostat is switched to cool mode and has a cooling set point below the room temperature reading. All honeywell thermostats that have batteries store the batteries in the control panel.

The purpose of which is to essentially switch off the heating unless temperatures inside get so low that something might. They have a pretty positive industry reputation, and many users testify to that. Locate and press the fan button on your honeywell.

The 'snowflake' symbol will be displayed if the 'frost protection' kit is installed and the temperature drops below what is set on the frost stat. I have a honeywell t8411 1028 thermostat. This delay is activated to protect your hvac system from short.

Locate the batteries by removing the battery compartment tray or cover or by removing the unit’s. Why is the cool on, heat on, snowflake, or flame blinking on the thermostat display? A power surge can trip the circuit your honeywell thermostat is on, leading to a shutdown.

The blinking “cool on” message on a honeywell thermostat display indicates that the system is restarting, batteries need replacing in the control panel, or a fault with the system. Weigh the risks before you decide to adjust the temperature limiting settings on your honeywell thermostat. The thermostat will indicate it is asking for the cooling to turn on when “cool on” or a “snowflake” in the display.