Hayward High Limit

This switch acts as a safety mechanism for your pool or spa heater. It automatically shuts down the heater if the water temperature exceeds 135°F to prevent overheating and potential damage to your equipment.

You likely need a replacement if your heater is failing to turn on, or conversely, if it continues to run even when the water temperature is clearly too high. If you suspect a faulty sensor, it is best to test the continuity of the switch with a multimeter.

This specific model is designed for systems requiring a 135°F limit. While it is a standard Hayward part, you should verify your heater’s manual or the label on your existing sensor to ensure 135°F is the correct temperature rating for your specific unit.

If you are comfortable working with basic pool plumbing and electrical components, this is a straightforward replacement. However, always ensure the power to the heater is completely shut off at the breaker before attempting any installation.

No, this is a set-and-forget safety component. It is designed for longevity and does not require regular maintenance, though it is good practice to inspect the wiring connections during your seasonal pool opening or closing.