Technical Data; Probe Filter - MasterCool 55744 Operating Instructions Manual

Congratulations on the purchase of the Mastercool 55744 Carbon Dioxide Gas Leak Detector, the most technologically
advanced instrument of its kind. The 55744's minimal power requirements, small size and high sensitivity combine to
create a tool which is easy to handle and ultra effective at locating even the most difficult-to-find leaks. Please read this
entire manual prior to operation to ensure trouble-free use of the 55744.

TECHNICAL DATA:

• Dimensions 8" x 2.5" x 2.25" (20.3 cm x 6.3 cm x 5.7 cm)
• Weight 15 oz. (425 grams) with Batteries
• Batteries 4 x 1.5V 'AA' Alkaline Batteries (6 VDC)
• Battery Life 20 hours
• Sensitivity (High) < 400 ppm at 350 ppm ambient
• Sensitivity (Low) < 4,000 ppm at 350 ppm ambient
• Sensor lifetime > 2 years
• Operating temperature 32 – 122°F (0 – 50°C)
• Warm up time 10 sec.
• Response time < 1 second
• Reset time < 1 second
• Probe length 12" (30 cm)
WARNING: The 55744 contains an optical sensor that must remain free of moisture and debris. Failure to operate the unit
without a filter may cause the sensor to become contaminated. This will result in a sensor malfunction as indicated by the
failed sensor alarm.
INSTRUCTIONS
1. Press the button to turn the unit on. Unit will beep 3 times and all LEDs will light.
2. The unit will warm up and self-calibrate for 10 seconds, after which a constant beeping will be heard.
3. Test the unit by exhaling gently into the probe tip. Human breath contains enough CO2 to cause a full-scale alarm in
High Sensitivity.
4. Unit turns on in the high sensitivity level (400 ppm). For zeroing into large leaks, change to the low sensitivity level:
Press the button twice (double-click like a computer mouse). The LEDs will scan from right to left and a sweeping
sound effect of high to low pitch will be heard. The sensitivity is now set for 4,000 ppm.
5. Double click again to change back to high sensitivity. The LEDs will scan from left to right and a sweeping sound
effect of low to high pitch will be heard.
6. To reset the unit to the ambient level of carbon dioxide, press and release the button. The LEDs will flash briefly to
indicate the reset. All levels of carbon dioxide less than the reset level will be ignored.
7. Move the probe towards a suspected CO2 leak at a rate of less than 2 inches (50 mm) per second, no more than ¼
inch (5 mm) away from the suspected source.
8. If a leak exists, the sound will increase in rate and pitch and the LEDs will indicate the relative leak rate.
9. To turn the 55744 off, press and hold the button for 1 second.
10. To conserve battery power, the 55744 will automatically turn itself off after 10 minutes of inactivity.

PROBE FILTER

The probe filter prevents dust and moisture from contaminating the optical characteristics of the sensor. It should be
replaced periodically. Occasionally, the filter may become obstructed with dirt, dust, or moisture. To determine if air is
flowing properly into the 55744 sensor, gently exhale near the probe tip. The human breath contains enough CO2 to
cause a full alarm in high sensitivity mode. If the unit does not alarm, replace the filter. If the filter has become moist due
to exposure to water or condensation follow this procedure to prevent moisture from contaminating the sensor:
1. Using a paper towel or shop rag, dry any moisture at the probe tip prior to unscrewing the probe tip cap.
2. Unscrew the probe tip cap to expose the filter.
3. With a paper towel or shop rag, soak up any excess moisture that may have collected on the filter and filter holder
prior to removing the filter. Also thoroughly dry both inside and outside of the probe cap.
4. Remove and discard the old filter, and replace with a new one.
5. Reassemble the probe tip cap. The unit is now ready for operation. Failure to dry the filter parts as described above
may result in further contamination of the new filter, and the possibility of residual moisture being drawn into the
optical sensor, causing a failed sensor alarm. If moisture is suspected of being drawn into the sensor, clean the probe
and sensor.
2 www.mastercool.com
English