Audible alarm
An audible alarm will sound if 35 PPM CO (or great-
er) is detected. The alarm frequency will increase
with higher concentrations. Check the LCD display
for actual level. While the alarm is sounding the unit
can not be turned off.
Back-Light
To activate the back-light press the
ON/OFF
key
quickly once. Do not hold down the key or the unit
will switch off.To turn off the back-light press the
ON/OFF
key quickly again.
Note:
Using the back-light decreases battery life.
LOW BATTERY INDICATION
Low battery indicator
If the battery voltage falls below a pre-set level the
symbol
“BAT”
appears in the display. Do not use the
instrument when this symbol is present. Replace the
battery immediately.
Troubleshooting
If the display fails to stabilize at around zero within a
few minutes this may indicate an expired sensor or a
sensor that has been exposed to excessive levels of CO.
If the symptom persists seek advice from an approved
service center.
Always check for correct operation before each use. Use
a known source of CO (e.g. a smoking match stick or a
recently extinguished flame) taking care to act in a safe
manner and not to expose the CO71A sensor to extreme
temperatures or CO concentration. If the unit does not
change as expected, return the unit to UEi or an approved
service center. DO NOT test using automotive exhaust as
the level may exceed the instrument range. This will poison
the sensor or decrease sensor life span.
If during use, you detect CO leaks, be sure you know the
appropriate actions to take to protect yourself and others.
Before switching off the instrument always expose it to
fresh air until the reading falls below 5 PPM. Note that the
readings fall much more slowly than they rise so you may
need to wait three minutes or longer.
Maintenance
Calibration
The CO71A must be calibrated annually at a certified
sevice location to maintain accuracy. Electrochemical
sensors are subject to long term drift that is corrected
during calibration. Refer to troubleshooting section of this
manual to check responce to CO. THIS DOES NOT verify
accuracy.
Specifications
No user serviceable parts. Re-calibrate every 12
months. Check for correct operation as described in
this manual before every use.
Concentration
of CO in Air
9 ppm
35 ppm
200 ppm
400 ppm
800 ppm
1,600 ppm
3,200 ppm
6,400 ppm
12,800 ppm
Inhalation Times and Toxic
Symptoms*
The maximum allowable
concentration for short term
exposure in a living area
according to ASHRAE.
The maximum allowable
concentration for
continuous exposure in any
eight hour period industry
according to MIOSHA.
Maximum concentration
allowable in any 15 minute
period according to OSHA.
Slight headaches, fatigue,
dizziness, nausea after 2 to
3 hours.
Frontal headaches within 1
to 2 hours, life threatening
after 3 hours. Maximum
allowable limit in flue gas
according to EPA and AGA.
Dizziness, nausea and
convulsions within 45
minutes. Unconsciousness
within 2 hours. Death within
2 to 3 hours.
Headache, dizziness and
nausea within 20 minutes.
Death within 1 hour.
Headache, dizziness and
nausea within 5 to 10
minutes. Death within 30
minutes.
Headache, dizziness and
nausea within 1 to 3
minutes. Death within 10 to
15 minutes.
Death within 1 to 3 minutes.
*The effects can vary depending on size, age, sex and health. UEi
is not liable for the accuracy of this information.
(Table 1)
039
BAT
Range:
0-999 ppm
Resolution:
1 ppm
Accuracy:
±(3% of r 1 ppm)
Audible Alarm:
Preset at 35 ppm
Visual Indication:
LCD and LED
Battery:
9V alkaline (NEDA 1604)
Ambient
Temperature:
32 - 104˚F (0 - 40˚C)
Warranty:
3 year
