Water Baths

Fill the water bath with distilled water so that the liquid level is approximately 1½ inches from the top of the tank when full anticipated load is placed in bath. For optimum results, the same fluid level should be maintained throughout the operating period.

All controls and indicators are located on the
front panel for ease of operation.

Power on/off - Controls line power to unit. Set to 1 position to turn on power, 0 position to turn off power.
°F or °C - Shows whether temperature is being displayed in Fahrenheit or Centigrade.
Display - During standby shows actual temperature; during setups, shows menu modes and values being selected.
Alarm - Lights to show that the backup controller is regulating the temperature rather than the primary controller.
Program - Lights to show that unit is in program mode rather than run mode; see menu below.
Heat - Lights to show when heat is being supplied to the chamber; cycles on and off as heat is requested by the controller.
Menu - Allows you to select the mode of operation. Each time you press the Menu button, the mode changes in this sequence:
- Select temperature units in °F or °C (display shows _C_F).
- Calibrate the unit (display shows CAL).
- Display the actual temperature of the chamber (normal mode of operation).
- The unit will return to normal operation, displaying the actual temperature, if you do not touch any control for a few seconds.
Set- When in the normal mode of operation, allows you to change the temperature setpoint. When in the _C_F mode, allows you to change the temperature units displayed. When in the CALibration mode, allows you to set the temperature offset to calibrate the unit.
Increase (∧) - After entering other than normal mode, increases the displayed value.
Decrease (∨) -After entering other than normal mode, decreases the displayed value.
Safety controller - Sets the Limit temperature above to the primary setpoint; should be set at a higher temperature than the setpoint to give the safety, control in the event that the primary control fails.Note: The safety control is not as accurate a control as the digital control.

See manual here:

Fisher Isotemp Water Baths