Frigidaire room air conditioners display a small, documented set of error codes: AS, ES and HS point to different failed temperature sensors, P1 means the internal drain tray is full, F1 and F2 indicate freeze protection has activated, and EC/LC signal a communication error. Most of these are either a simple drain fix or point clearly toward a sensor needing replacement.
The documented codes
| Code | What Frigidaire says it means |
|---|---|
| AS | Room temperature thermistor failed |
| ES | Indoor defrost thermistor failure, or humidity sensor failure |
| HS | Air discharge thermistor failed |
| P1 | The bottom tray is full |
| F1 | Freeze protection engaged |
| F2 | Freeze protection |
| EC | Communications error |
| LC | Communication error between indoor/outdoor units |
P1: Bottom tray full
This is the one code on this list that is not a sensor fault. Many Frigidaire units collect condensation in an internal tray during operation, and P1 simply means that tray needs draining before the unit will continue running.
- Locate the drain plug
Usually on the back or base of the unit — check your model’s manual for the exact position.
- Drain the collected water
Have a shallow container ready, since a full tray can hold a meaningful amount of water.
- Power cycle after draining
Some models need a power cycle to clear the code even after the tray is empty.
AS / ES / HS: Thermistor faults
These three codes each point to a different temperature sensor (thermistor) in the unit — room temperature (AS), indoor defrost or humidity (ES), and air discharge (HS). Frigidaire’s documented first step for these is the same: unplug the unit from power for up to 30 seconds, then plug it back in and see if the code clears. If it returns, this points to the specific sensor mentioned in the code and needs a technician, since these sensors are not typically a user-serviceable part.
F1 / F2: Freeze protection
These codes indicate the unit’s freeze protection has engaged, a safety feature that stops the compressor when conditions could cause ice to build up on the coil (running the unit in very low outdoor temperatures, or with badly restricted airflow, are common triggers). Check that the air filter is clean and that nothing is blocking the intake or outlet before assuming a fault.
EC / LC: Communication error
Both codes point to a communication problem — EC more generally, LC specifically between the indoor and outdoor sections on split-type units. A power cycle of the full system is the first step; if it returns immediately, the wiring or control board connection between components needs inspection.
When to call a technician
Any thermistor code (AS, ES, HS) or communication code (EC, LC) that returns after a full power cycle is not something to keep resetting repeatedly — it means the underlying sensor or connection has actually failed.
Stop and call a qualified appliance technician or electrician if you find scorched or melted wiring, smell burning, see water that has reached electrical components, or if the fault returns immediately after a repair. Never bypass a safety device — thermal fuses, door interlocks and flood switches fail for a reason, and defeating one converts a broken appliance into a fire or flood risk.
