Mastercool 55900 Intellasense Ii Refrigerant Leak Detector

Name: Mastercool 55900 Intellasense Ii Refrigerant Leak Detector
Brand: Mastercool
SKU: JB-MSC-55900
Price: 138.41 USD
Availability: InStock

SKU: JB-MSC-55900

4.1 (7 reviews)

$138.41$230.69SAVE 40%

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Description Mastercool 55900 Intellasense Ii Refrigerant Leak Detector “Super Sensitive Function” allows the unit further sensitizing beyond the standard settings for locating small leaks with gases such as R1234yf and R407C SENSITIVITY: HIGH ≥ 0.15 oz/yr (4 g/yr) MEDIUM ≥ 0.25 oz/yr (7 g/yr) LOW ≥

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Product Details

Mastercool 55900 Intellasense Ii Refrigerant Leak Detector
- “Super Sensitive Function” allows the unit further sensitizing beyond the standard settings for locating small leaks with gases such as R1234yf and R407C
- SENSITIVITY:
  - HIGH ≥ 0.15 oz/yr (4 g/yr)
  - MEDIUM ≥ 0.25 oz/yr (7 g/yr)
  - LOW ≥ 0.50 oz/yr (14 g/yr)
- PROBE:
  - Intelligent tip design that senses the condition of the environment, to eliminate the potential of false alarms.
  - Flexible 15.5” probe for difficult to reach locations
- DISPLAY:
  - Six vertical LED’s (red, yellow or green) display the following information to the user such as:
    - Relative signal level of the detected leak
    - Selected sensitivity range (low/medium or high) of the unit
    - Diagnostic information: low battery, interference/wait, contaminated atmosphere, readiness of the unit or fault
      conditions of the unit
- REFRIGERANTS: Detects all refrigerants (CFC’s, HCFC’s, & HFC’s and blends)
- SENSOR LIFE: 2000 hours
- SENSING ELEMENT: Heated tin oxide
- OPERATING TEMPERATURE RANGE: 0 to 140˚F
- RESPONSE TIME: Less than 1 second
- POWER: 2 C Alkaline 6000 mAh batteries
- BATTERY LIFE: 30 hours
- WEIGHT: 1.08 lbs
- KEYPAD FUNCTIONS:
  - ON/OFF: Press the ON/OFF button to turn the unit on or off
  - VOLUME/MUTE: Press the VOLUME/MUTE button to control the volume of the unit
  - H M L SENSITIVITY: Press the H M L SENSITIVITY button to select the desired sensitivity level
  - PEAK/HR/LR: The PEAK/HR/LR key serves a dual purpose:
    - (1) To assist the user in locating the “largest leak” in a system with multiple leaks present.
    - (2) To enable the user to switch between HR (high range) and LR (low range) modes.
Warning: California's Prop 65

Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

From the published reviews

Customer feedback at a glance

Editorial summary of 7 customer reviews, reviewed September 30, 2026. These are individual experiences, not independent product tests.

Customers appreciate the flexible probe, adjustable sensitivity and visual or audio alerts. Some mention a learning period, and one reports excessive sensitivity in unclean air that improved with a lower setting.

Questions about the feedback

Is there a learning period with the sensitivity controls?

Some customers describe practicing with the controls or learning the LED indications. One lowered the sensitivity when surrounding air caused excessive responses. Their experiences do not establish detection accuracy or replace the operating instructions.

Read the original reviews behind this summary (7)