Humboldt H-4239A Hydrometer Waterbath - Manual (Page 5)

Operation
Once set-up has been completed and the water bath has been filled with water.
The bath is ready for operation.
To power on the unit, FIRST, turn on the power for the chiller. This switch is
located at the bottom of the back of the chiller. This switch can be left on, as the
operation of the chiller is controlled by the controller located on the water bath.
However, if this switch is not turned on, the unit will not cool.
Once the chiller has been turned on, Push the POWER switch down on the water
bath to turn the controller on. The heating indicator to the left of the POWER
switch will illuminate and show you the current temperature of the bath on top
of the controller in red and the current set point, on the bottom in green.
Use the arrows on the controller to set the desired temperature you would like to
operate the bath at, i.e. the set point. The set point is indicated by the bottom
number on the control, which is in green. Humboldt Hydrometer Jar Water Baths
are capable of heating and cooling the bath.
Once you have set the setpoint for the bath, either the heating element or the
cooler will begin to heat or cool the bath. This will be indicated by a flashing
light to the right of the actual temperature reading, the top number on the
controller. Once the bath temperature has stabilized at the desired temperature,
the thermostat will call on the heater or the cooler to maintain that temperature.
Typical time to cool a bath from 85°F (30°C) to 68°F (20°C) is 4 hours.
Digital Controller Factory Setup
H-4239A, Hydrometer Jar Water Bath, 110V 50/60Hz models come set to °F
H-4239A.4F, Hydrometer Jar Water Bath, 220V 50/60Hz models come set to °C
If you desire to change this setting, hold the two arrow buttons in at the same
time and hold for 5-10 seconds. Pushing the blue scroll button allows the display
to advance to the next setting, while using the up and down arrows you can
change the actual setting.
WARNING
UNIT SHOULD NEVER BE USED WITH LESS THAN 8 INCHES (200mm)
OF WATER FROM THE TOP OF THE SHELF. IF THE UNIT IS
EMPTIED WHEN HOT, IMMEDIATELY REFILL WITH A MINIMUM OF
8 INCHES (200mm) OF WATER