Jacuzzi Z Builder Series Mechanics And Repair page 31

WHAT IT DOES:
Typically, when you power up the sensor the board looks at both Over Heat
Sensor and the Temperature Sensor and compares them. It should see no
significant difference and the range should be within normal range. If it see
outside the tolerances, depending on which system you have, it will notify you of
the problem and fail to turn the spa on. If the temperatures are close, it continues
it's self test.
To Replace:
The Temperature sensor inserts into the filter box. Simply pull down and the seal
will break and the sensor will come out. If you have water in the spa, it will pour
out. You usually can switch with the new sensor fast enough to minimize water.
The Over Heat sensor clips on the heater. Again, simply pull out.
Connection to the board:
The most common connection of the sensors to the board is a joint plug where
both the temperature and high limit sensor pair together. To release the wires
from the plug do this: Unfold a paper clip. Note on the plug the ends of the wires
inside the plug are rectangular windows. By pressing down on the wire
rectangular ends and pulling the wire, the end will release from the plug and slide
out exposing the ends.
If you have black ends to your cord there is a simple clip to press to release. The
biggest problem is the clip is hard to see and sometime to reach. If you look on
the top of the clip you will see the lever to press down to release. I use a small
screwdriver to press down and pull out..