Carrier Thermostat Displays Error Code E3

E3 means low pressure of refrigerant.

The E3 error code displays when an Abnormal Operation Protection Error has occurred and activates to protect the unit from damage. This error code will require service.


HOPE THIS HELP!

https://acerrorcode.com/dometic-thermostat-error-codes.html

I asked Mr. Google " carrier e3 error code", and I found this.

The outdoor thermostat is in error, not connected, or shorted out. This code is displayed only if auxiliary heat and/or cool lockout feature is enabled.

What this means is that your o.d. unit has a component failure. The smeel you have inside is probably you electric heat elements that are energized. And if they haven't been energized in a while, its burning off some debris.

Installed how recently, by whom? Call installer!

Error Code:
E1 Loss of communication between the Single Zone LCD thermostat and the mod-ule board. LCD will cycle between E1 and the previous mode setting. System
will shut down.
E2 Open circuit or out of range Indoor Temperature Sensor. Heating and cooling
operation will be locked out. Fan operation can continue to operate.
E3 Shorted Indoor Temperature Sensor. Heating and cooling operation will be
locked out. Fan operation can continue to operate.
E4 Open circuit or out of range Outdoor Temperature Sensor (select models). Heat
Pump operation will be locked out. Air Conditioner, Fan and Furnace operation
can continue to operate.
E5 Open circuit or out of range Freeze Sensor. Air conditioner mode of operation
will be locked out. Furnace, heat strip, heat pump and fan mode of operation can
continue to operate but displays the last temperature set-poi

Bad Thermastat replace it.

That blinking light may be the diagnostic light. Count the blinks next time it fails. Carrier units will have two different blinks depicting the error code such as one blink followed by a pause than 3 blinks giving you an error code of 13. Then look at the wiring diagram, it will have an error code chart telling you where to start with your diagnosis. You already know that if you remove the cover it erases the error code, so look thru the small window first.

Error code 12 is blower on after power up. Meaning: after you turn on power to the furnace for aprox. 60-90 seconds the blower will run. The blower should then shut down and the furnace should go through the start up process, providing that the thermostat is set for and calling for heat. If the furnace fails to start after blower shut down there should be a new fault/error code. However if the blower continues to run longer then 90 seconds and continues with the same fault code more then likely the circuit board is bad. Please let me know if this was helpful and give me a rating. Good luck.

I have the same type of Aprilaire humidifier unit with automatic temperature sensing control. My unit also displayed the 'E3' code. The HVAC technician was on site today and replaced the temperature sensing unit that is located outside the house. The humidifier is functioning normally once again.

sounds like the high limits tripped