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  • Large, four‐tiered LCD simultaneously displays CO concentration, air temperature, and relative humidity with date and time
  • Easy to use, intended for indoor air quality monitoring
  • Ranges
    • Carbon monoxide: 0 to 999 ppm, ±2 ppm accuracy
    • Temperature: 14 to 140˚F, ±1.2˚F accuracy
    • Relative humidity: 10 to 90% RH, ±5% RH @ 25°C accuracy
  • Visibly bright LED indicates active monitoring (green) or surpassed CO alarm threshold (red)
  • Extra loud audible beeper alarm level meets UL 2013 Standard (>85dB @ 3 meters); default alarm threshold at 30ppm (user adjustable)
  • Designed with Electrochemical CO sensor
  • Record/Recall Max reading for CO concentration
  • CO calibration function in fresh air
  • Internal memory for manually storing up to 99 readings with recall function
  • Desktop style

What's in the Box

  • Universal AC adapter (100V-240V)
  • Multiple plug types (US, EU, UK, AUS)

The Extech CO50 Carbon Monoxide Monitor is a desktop, three‐in‐one instrument that monitors and measures temperature and humidity in addition to carbon monoxide. The fully calibrated instrument will provide years of reliable service in a number of applications that require monitoring indoor air quality and potential carbon monoxide problems such as gas appliances, out-of-adjustment burners, blocked chimneys, gas or kerosene space heaters, idling vehicles in garages, gas-powered generators or small-engine equipment operated in enclosed areas, and furnaces and water heaters with inadequate ventilation.

The Extech CO50 measures carbon monoxide concentration from 0 to 999 ppm, air temperature from 14 to 140˚F and relative humidity from 10 to 90% RH and simultaneously displays the results on the large, four-tiered LCD display. A highly visible, bright LED indicates active monitoring (green) or surpassed CO alarm threshold (red) and the extra loud audible beeper alarm meets UL 2013 Standard (>85dB @ 3 meters). All alarm setpoints are user adjustable. An internal memory stores up to 99 readings for later recall.