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How to Replace a Flow Temperature Switch on the IntelliChlor IC20

Beach Resort Swimming Pool image by Mohd Haka Khambali from

Electrolytic chlorine generation is a method of water sanitation for swimming pools. The IntelliChlor line of chlorine generators from Pentair is popular with consumers because of their user-friendly automated features. Even the most dependable device requires maintenance and occasional repair, however. If you’ve determined that your IntelliChlor IC20 needs a new flow-temperature switch, a complete installation kit is available from the manufacturer.

Turn off all power to the pool pump and chlorine generator.

Locate the flow-temperature switch cover on the IntelliChlor cell. Unscrew the cover with a small Phillips screwdriver and remove it to expose the switch.

Unwrap the cable from around the switch. Cut the cable close to the old switch so you will have enough wire to connect to the new one. Strip two inches of insulation from the outside of the cable coming from the cell. Don't strip the smaller wires inside. Position the cable out of the way.

Take note of the direction of the arrows on the nut-shaped body of the switch. Use a ½-inch open end wrench to unscrew the switch assembly from the cell. Be careful not to damage any part of the cell body with the wrench.

Install the new switch by carefully threading it into the hole in the cell. Tighten the switch by hand as far as you can. Use a wrench to finish threading the switch almost fully into the cell. Align the arrows on the switch with the direction of water flow. The center arrow should point directly to the center of flow.

Strip 2 inches of insulation from the cable of the new switch if it isn't already stripped. Don’t strip the smaller wires.

Use the special water-tight connectors supplied with the installation kit to connect the new switch to the cell. Pair the red and black wires from the switch with the red and black wires from the cell. Pair the green and white wires from the switch with the green and white wires from the cell. If your cell doesn't have the green and white wires, put the wires from the switch into the water-tight connector by themselves. Crimp the connectors firmly with pliers.

Wrap the cable around the replacement switch so it’s out of the way. Replace the switch cover and tighten the screw. Turn the power back on to the pool pump and chlorine generator.


Consult the manufacturer’s instructions for the complete wire pairing and connecting sequence, which depends on the type of switch you’re replacing.

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