RDS 2 flashes Control board internal fault (leak detection board)

What the control is telling you

Red LED flashes 2 times, then off 5 s: the A2L board has found a problem with the detection system.

Applies to: R-32 air handlers with refrigerant detection system (A2L PCB + R32 sensor): AMST, AWSF/AWST, ACSF

Likely causes

• Internal fault on the A2L control board
• Sensor or connection problem (to be ruled out)

Test and repair steps

1. Unplug and reconnect the R32 sensor, then power cycle.
2. If the board shows normal or delay mode, the issue is gone.
3. If not, unplug the sensor and leave it unplugged, then power cycle.
4. Still 2 flashes = replace the board. Changes to 3 flashes = replace the sensor.

Models that show this code

4 models in Goodman/Amana R-32 AMST/AWSF/ACSF air handlers

Other codes on the same units

• RDS 3 flashes R32 sensor communication fault
• RDS 4 flashes R32 sensor internal fault
• RDS fast flash R-32 leak alarm (or system verification test)
• RDS steady on Delay mode after leak alarm or fault