Chapter Six: Sensors - Jacuzzi Z Builder Series Mechanics And Repair

Chapter SIX: SENSORS

TEMP/OH SENSORS:
HOW IT WORKS: Sensors work by reacting to temperature at the bulb. As the
temperature raises or lowers, the resistance inside the sensor bulb changes. The
board reads the resistance of the temperature and knows what the temperature
of the spa is. That is how is determines spa temp. Some spas have their
temperature sensor inserted into the actual spa. Others in a housing inserted into
the spa. Jacuzzi's most common design is the sensor inserts into the side of the
filter box.
The second sensor is the Over Heat sensor. If that sensor raises above a certain
threshold, usually 112-115 degrees, it shuts the spa down. It is clipped against
the heater.
Typical Resistance Values for Sensors and the water temperature.
Temperature Resistance