The A771 is a CO adapter designed to work with your DMM to measure ambient air CO. Can also be used as a personal COalarm.

National Ambient Air Quality Primary Standards in the US call for less then 9 ppm carbon monoxide for an 8 hour average during any 12 month period.

Concentrations of 1 to 2 ppm may be found in homes with a normally operating gas furnace to well over 1,000 ppm in homes with a faulty furnace.

Just 200 ppm CO over 2 to 3 hours can cause slight headache, fatigue, dizziness, and nausea.

Carbon Monoxide testing is a crucial service provided by HVAC/R technicians.

The A771 is an advanced state-of-the-art Carbon Monoxide monitor that may be used to measure levels of carbon monoxide (CO) in the parts per million (ppm) range when used with a digital multimeter (DMM).

Carbon Monoxide (CO) Measurement	Range 0 - 1999ppm
Accuracy	± 5ppm or 5% of reading whichever is greater
Resolution	1ppm
Output	1mVDC / 1ppm CO into 10M Ohm impedance
IR Printer Port	No
Flue Probe	No
Internal Pump	No
Combustible Gas Leak Detection	No
Backlight	N/A
Alarm	Audible
Power Supply	9V Alkaline Battery
Dimensions	6.5" x 2.1" x 1.2" (165 x 55 x 30 mm)
Weight	7.23oz (205g)
Warranty	3-year limited warranty 2-year sensor warranty

	706 Advanced High CO Meter	707 Advanced CO Meter	770 Carbon Monoxide Monitor	775 Ambient CO & Combustible Gas Leak Detector	A771 Carbon Monoxide Adapter for DMMs
Measurement & Ranges	CO: 0 to 9,999 ppm, over 9,999 ppm readout in % 1.0 to 9.9 (9.9% = 99,999 ppm)	CO: 0 to 9,999 ppm	CO: 0 to 9,999 ppm	CO: 0 to 2,000 ppm Methane: >50 ppm	CO: 2,000 ppm
Quick & Easy Operation	Yes	Yes	Yes	Yes	Yes
Display	Easy-to-read, 3-line LCD	Easy-to-read, 3-line LCD	Easy-to-read, 3-line LCD	Easy-to-read, 3-line LCD	N/A
Printing Capability	Use Optional A740 IR Printer for real-time, date stamp	Use Optional A740 IR Printer for real-time, date stamp	N/A	N/A	N/A
Alarm	N/A	N/A	Visual & Audible	Visual & Audible	Visual & Audible
Other	Pump-driven for fast response. Push-on fittings for fast and easy use.	Pump-driven for fast response. Push-on fittings for fast and easy use.	Tilt-stand on back.	Visual & audible tic rate to pinpoint leak. 16” goose- neck probe.	Use with any DMM with 2 1/2 digit LCD, 2 or 4 V DC range, and 10 M OHM or greater input impedance.
Applications	Test forklift exhaust gasses for the presence and location of CO leaks.	Measure CO levels in the flue, and test ambient CO levels in homes, offices, and other confined spaces.	Measure and monitor ambient CO levels in homes, offices, and other confined spaces.	Measure ambient CO levels. Check for CO in and around combustion sources; locate combustible gas leaks.	Measure ambient CO levels in residential and commercial areas.