Replaced the batteries. The led flashes RED-YELLOW-GREEN. Is this normal or is there a problem with the smoke alarm.
The PG9936 flashes that sequence in two scenarios.: On power-up, and while tampered. When tampered it will have a Red, yellow, green flash sequence every
12 seconds.
Make sure the sensor is connected securely to its mounting base. A table describing the LED status can be found in the manual here: