How To Change an AutoPilot Tri-Sensor

This guide will walk you through replacing the APA0003.The Tri-Sensor (APA0003) for the AutoPilot salt chlorinator will occasionally fail. When the Tri-Sensor fails the chlorinator will stop generating chlorine. 

1. TURN OFF THE POWER TO THE TIMER BOX. There should be a circuit breaker before the timer box where the power can be turned off. This is important because you do not want the pump running when you remove the existing sensor.

2. Open the air relief valve located on top of the pool filter. This will release the pressure from the system and make it easier to remove the Tri-Sensor.

3. Disconnect the AutoPilot Tri-Sensor from the power center. Press the two white tabs inward to remove the cable plug.

4. With a phillips head screwdriver, remove the two screws retaining the Tri-Sensor in the tee joint of the manifold.

5. Note the direction of the flow tab. The flow tab should be pointing in the same direction as the flow arrows on the manifold.The Tri-Sensor must be installed in the same orientation when it is replaced.

6. The AutoPilot Tri-Sensor can now be pulled out of the tee. Firmly grip the Tri-Sensor assembly with a large pair of channel locks or strap wrench. Twist the Tri-Sensor back-and-forth while simultaneously pulling the Tri-Sensor straight out of the tee joint.

7. Line up the new AutoPilot Tri-Sensor (APA0003) on the tee. Make sure the flow tab is pointing in the direction of the flow.

8. Press the Tri-Sensor into the tee and make sure the holes from the sensor match up with the holes on the tee.

9. Tighten the two screws and secure the Tri-Sensor to the tee.

10. Plug the Tri-Sensor (APA0003) cable back into the receptacle on the power center.

11. Turn on the power at the circuit breaker.

12. Any air in the piping should be coming out of the open relief valve. When water starts to spray out of the relief valve, shut the valve off.

13. After a couple minutes the AutoPilot control box should display the output level, time, and temperature.

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