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Extech

Extech CO240 - Indoor Air Quality Meter - Handheld CO₂, Temperature, Humidity, Dew Point & Wet Bulb Monitor with Audible Alarm

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Availability: In Stock.
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Arrives Sunday, Jan 11
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Features

  • Comprehensive Air Quality Monitoring - Measures CO2 concentration, air temperature, relative humidity, dew point, and wet bulb temperature for complete indoor environmental assessment.
  • Maintenance-Free NDIR Sensor - Utilizes a non-dispersive infrared (NDIR) sensor for accurate and reliable CO2 measurements without the need for regular calibration.
  • Audible CO2 Alarm - Features a user-settable high CO2 alarm with an audible beeper to alert users when concentration levels exceed safe thresholds.
  • Data Logging Capabilities - Includes software and USB cable for real-time data logging to a PC, enabling detailed analysis and record-keeping.
  • Portable and User-Friendly - Compact design with a large LCD display, tripod mount, and includes six AAA batteries, USB cable, PC software, and a soft carrying case for convenience.
  • Dual display of Carbon Dioxide (CO2) concentrations and Relative Humidity, Temperature, Dew Point, or Wet Bulb
  • Maintenance free NDIR (non-dispersive infrared) CO2 sensor
  • Audible CO2 warning alarm when concentration level exceeds high user set point
  • Min/Max CO2 value recall function
  • Data Hold, Auto Power Off (with disable), Low battery indicator

Description

The Extech CO240 Indoor Air Quality Meter is a versatile handheld device designed to monitor key indoor environmental parameters. Equipped with a maintenance-free NDIR CO₂ sensor, it provides accurate measurements of carbon dioxide levels, air temperature, relative humidity, dew point, and wet bulb temperature. The user-settable high CO₂ alarm ensures that users are alerted when air quality deteriorates beyond acceptable limits.

Brand: Extech


Style: CO240


Power Source: Battery Powered


Color: Green/Orange


Product Dimensions: 8.3"D x 2.4"W x 1.6"H


Item Weight: 0.2 Kilograms


Alarm: Audible


Operating Humidity: 85 percent


Sensor Type: Non Dispersive Infrared


Global Trade Identification Number: 02


Brand: ‎Extech


Style: ‎CO240


Power Source: ‎Battery Powered


Color: ‎Green/Orange


Product Dimensions: ‎8.3"D x 2.4"W x 1.6"H


Item Weight: ‎0.2 Kilograms


Alarm: ‎Audible


Operating Humidity: ‎85 percent


Sensor Type: ‎Non Dispersive Infrared


Global Trade Identification Number: ‎02


Material: ‎Carbon


Number of Items: ‎1


Manufacturer: ‎Extech


UPC: ‎793950502402


Part Number: ‎CO240


Item Weight: ‎7 ounces


Item model number: ‎CO240


Batteries: ‎6 AAA batteries required. (included)


Is Discontinued By Manufacturer: ‎No


Item Package Quantity: ‎1


Number Of Pieces: ‎1


Included Components: ‎Six AAA batteries, USB cable, PC software, case


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Alkaline


Warranty Description: ‎2 years


Date First Available: January 29, 2015


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Jan 11

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Used for work. Worked well.
Used for work. Worked well.
Reviewed in the United States on November 27, 2024 by Keaton Sweeney
    • Inaccurate, unstable, unreliable and now failed with multiple error codes after 6 weeks!
A dreadful, overpriced, unreliable, unstable and inaccurate meter. Would give a zero or negative * rating if I could. DO NOT BUY THIS EXTECH CO2 meter. I bought three different CO2 monitors. One power connected for the house from Gain Express, one battery powered from NewishTool, and then the Extech because it was a name brand and more portable. Unfortunately right from the start the $300 Extech was unstable and needed constant calibration. Far worse than the $120-$140 units. Then last week it started reading 6000 ppm (in the outdoors!) after being calibrated just a few days earlier. Then this week it started throwing up error codes. And reading 136 ppm 5 minutes after being calibrated outside to 400 ppm. Meanwhile the other two inexpensive units are stable, consistent and work well. Extech should be ashamed for selling such a piece of junk. I would send it back except it is past the return date. Stuck with it. Absolutely do not buy Extech. This is not the first Extech unit that I have had problems with. We have their similar VOC and HCHO testers and they have been problematic too. I bought on reputation again and clearly made a mistake. Have finally learned to avoid Extech. ... show more
Reviewed in the United States on March 3, 2021 by GI10
    • Convenient
Convenient little unit. I bought it for energy audits of buildings.
Reviewed in the United States on November 23, 2018 by ErToro
    • Purchased Twice, Broken Twice
Review Image by Amazon Customer Amazon Customer
Review Image by Amazon Customer Amazon Customer
We already own this equipment. It's very sensitive and you can't hold it within a 4' range of your breathing zone or it will pick up the CO2 you exhale. The one we own bit the dust giving us an error code E-01 (board failure) and the other, the reading will continue to drift upward until it maxes out. We purchased a replacement and upon opening it, we had the error code E-01. The item was returned and upon opening the replacement item, we found an item which appears to have also previously been returned to Amazon (as the batteries were loose, no longer packaged, inside the box as they were on the last item. This time around, the top of the equipment (which houses the sensitive board) was smashed. I would not recommend this equipment, but unfortunately, I do not have a recommendation for a better piece of equipment. ... show more
Reviewed in the United States on February 14, 2022 by Amazon Customer Amazon Customer
    • Temperature not accurate..
1. CO2 - The reading is accurate but sometimes if you accidentally shake the meter, reading will become wrong. Really sensitive type of meter. 2. Temp - I think is a bit off about +1 Celsius when i compared to my calibrated Fluke 971 meter. The response time too slow and you need to wait a while to getting the correct reading. In my case i need a fast response since i’m doing an energy audit and of course lots of points need to measured. It took me more days to complete a task due to slow of response time. ... show more
Reviewed in the United States on June 29, 2019 by MoHakim
    • Nice meter for the price
Good CO meter that reads temperature and humidity very quickly too!
Reviewed in the United States on July 25, 2022 by bristu57
    • Pretty good out of the box
Bought this mostly for the CO2 meter and that is within 10ppm of our nist calibrated meters so I'd say that is pretty good right out of the box. As other reviews have mentioned it is very sensitive so be sure you are several feet away from it while the reading settles out. I didn't test the temperature and humidity but they appeared to be within reasonable values. ... show more
Reviewed in the United States on May 4, 2023 by Angela

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