What AS Means
On Frigidaire room air conditioners (window, wall and portable units), Frigidaire's error code guide lists AS as a failed room temperature thermistor. Without a valid room reading, the control cannot decide when to cycle cooling on and off.
Common Causes of AS
- Failed room temperature thermistor
- Loose or corroded sensor connector
- Control board fault
🔧 One Safe Check You Can Try
Turn the unit off first, then unplug it (or switch off its breaker for hardwired or 230V units) for about 30 seconds, as Frigidaire recommends. Restore power and see whether AS returns. If it does, leave the unit off and book service — the sensor sits inside the cabinet near live wiring.
⚠ Why You Shouldn't Go Further Than That
- The thermistor is mounted inside the chassis next to the control board and powered wiring.
- Room air conditioners contain a sealed refrigerant system and capacitors that can hold a charge.
- Damage caused during a repair attempt may not be covered by your warranty — check your warranty terms first.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.