How To Check an AutoPilot Tri-Sensor


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If the AutoPilot has stopped working and the digital screen displays the message "Purifier Off- Check Flow", there is an issue with the flow. It may be caused by a dirty filter or it may be caused by a defective Tri-Sensor. The following steps will provide a guide on how to check the AutoPilot Tri-Sensor.

Things You'll Need

Step by Step


Step 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 Tri-Sensor.

Step 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.

Step 3

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

Step 4

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 reinstalled.

Step 5

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.

Step 6

Inspect the thin metalic paddle for erosion and straightness. If there is erosion or damage to the metalic paddle, the Tri-Sensor needs to be replaced. If not, the existing Tri-Sensor can be reinstalled.

Step 7

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

Step 8

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

Step 9

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

Step 10

Turn on the power at the circuit breaker.

Step 11

With the pump running, 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.

Step 12

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



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