Maintenance - MasterCool 55744 Bedienungsanleitung

SENSOR
An 55744 sensor is designed for a long, trouble-free life. The sensor is tested and calibrated automatically each time the
unit is powered on. A failed or failing sensor will be indicated 3 seconds after power-on by a two-tone alarm and all LEDs
flashing.
CLEANING THE SENSOR
If moisture is suspected of contaminating the sensor, the probe and sensor may be cleaned using this procedure.
1. IMPORTANT: Remove the sensor from the instrument as directed.
2. Remove the probe tip cap and filter from the probe tip.
3. Blow compressed air into the probe tip to remove any residual moisture from the probe.
4. Blow compressed air* into the inlet and outlet ports of the sensor.
5. Place a few drops of distilled water or isopropyl alcohol into both the inlet and outlet ports of the sensor.
6. Blow compressed air* into the inlet and outlet ports of the sensor to remove any remaining liquid and thoroughly dry
the exterior of the sensor.
7. Install the sensor, and insert a new filter into probe tip. The unit should now operate properly.
* Note: Do not exceed 50 psi pressure. Doing so may result in the loss of the small o-rings in the inlet and outlet ports of
the sensor.
SENSOR REPLACEMENT
In the event of a failed sensor (as indicated by the Failed Sensor Alarm), cleaning or replacement of the sensor is neces-
sary. First, clean the sensor as directed. If an alarm is still heard, the sensor must be replaced. To replace the sensor:
1. Turn the power off.
2. Remove the sensor compartment cover by loosening the sensor compartment cover screw.
3. Remove the 2 screws holding the sensor in place with a 1.5 mm hex wrench.
4. Grasp the old sensor with your fingers near the screw holes and firmly lift out of the sensor compartment.
5. Firmly press the new sensor into the compartment, noting alignment of the sensor connector tab and gas ports of the
sensor with the mating features in the instrument.
6. Firmly tighten sensor in place with 2 screws and 1.5 mm hex wrench.
7. Replace and fasten sensor compartment cover.
Replacement Sensor Kit: Part Number ELS-7CO2
BATTERIES
• The left-most (blinking) LED indicates the battery life, and dims when the batteries approach end of life. Less than
one hour of battery life remains when the LED is completely dark.
• When the batteries no longer contain enough energy to power the instrument reliably, a five second tone will be
heard, after which the 55744 will power itself off.
• If the unit is left on unattended, it will automatically turn off after about 10 minutes to conserve batteries.
BATTERY INSTALLATION AND REPLACEMENT
1. Turn the power off.
2. Remove the battery cover from the back of the instrument by loosening the battery cover screw and lifting the
battery cover off.
3. Insert 4 size 'AA' alkaline batteries, observing proper battery polarity.
4. Replace battery cover and tighten battery cover screw.

MAINTENANCE

The 55744 should provide years of service with little maintenance aside from changing batteries, filters, and sensors. The
case may be cleaned with a shop towel moistened with water and a mild detergent. Do not use solvent of any kind.
WARNING: This product contains one or more chemicals known to the State of California to cause cancer,
birth defects or other reproductive harm.
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