The Carrier comfort zone thermostst displays the

Question edited for clarity and spelling.

Disconnect from the mains supply for an hour and then fully reprogram.

https://www.google.com/search?q=Comfort+II+thermostat+changes+all+the+zones+to+%22out%22

COMFORT ZONE II - E. Smith Heating & Air Conditioning

https://esmithair.com > uploads > 2015/03 > Comf...
PDF
From the normal operation mode, press the Hold, Out, and All Zone buttons in that order to program all zones to an unoccupied status. Until you return, the air ...
24 pages

..

If it 2 degree cooler then that's fine .adjust your thermostat 2 degrees higher so you will get the temperature

Hi Anonymous,
For all wall mounted and Artcool split system codes

Error code = C1 or CH1
Flashing Light = 1
Fault = Indoor temperature sensor open or closedcircuit.
Display = Indoor.
Indoor Operation = ON

Error code = C2 or CH2
Flashing Light = 2
Fault = Outdoor temperature sensor open orclosed circuit.
Display = Indoor Outdoor.
Indoor Operation = ON

Sounds to me like a bad damper or a bad zone panel. Turn tstat off and call for cooling on zone 2. Then see if your still getting cool air to zone 1.( where the main tstat is)

If you need further help, reach me via phone at https://www.6ya.com/expert/thomas_092728000e6acb79

Comfort Zone heaters do not have a display board, they only had thermostat knobs.

Is it possible that you have a different model of heater?

Hi. I have the Comfort zone 1500 (cz 1500) and just ran into this AO5 problem. Turns out the thermostat was set lower than the actual room temperature. I just turned up the heater temp and it kicked right on. Hope this helps!

This .pdf file may be of help to you:
www.brivis.com.au/.../Carrier%20Comfort%20Zone%20II%20Owner's%20Guide.pdf
Perhaps you could get some help from Carrier Support here:
http://www.residential.carrier.com/support/index.shtml
I noticed they have an option of talking to an engineer, and perhaps they could explain how to reset or set the unit.
Hope this helps.

The stat that works is called the main and the other two are called slave stats. The stats must be set to heat or cool the same as the main. If you want one room to cool and one to heat , sorry. Need to upgrade to auto changeover. Is this AC actally a Heat pump?

I reset the circuit breaker to the panel and everything is good now.

Is this an electric or gass furnace - Eather of these can can have this problem its most recomendable that you call a seviceman .
in the case of electric furnace you may requier a new heat sequencer. And in the case of gass you may requier a new relay.