UEi AQM4 User Manual

HOLD

MIN
MAX
AVG

CAL

REC
Re call

INSTRUCTION MANUAL

TA

CO

2

DP

CO

AM
PM

WBT

O

C

O

F

%rh

AQM4

Indoor Air Quality Meter

1-800-547-5740 • Fax: [phone]

Email: [e-mail]

INTRODUCTION

Thank you for purchasing the UEi AQM4 IAQ
meter. The meter measures CO² levels, CO
levels, air temperature, dew point, wet bulb
temperature, and humidity. The AQM4 is an
ideal instrument for indoor air quality (IAQ)
diagnosis.

Poor indoor air quality causes tiredness,
inability to concentrate, and even illness
(ex. Sick Building Syndrome). IAQ monitoring
and surveying especially for CO² levels
and air ventilation has become widely
applied in public offices, classrooms,
factories, hospitals, and hotels. It is also
recommended for regulating standards of
industrial air quality in some countries.

The portable AQM4 uses NDIR (non­dispersive infrared) technology for CO²
measurement to ensure reliability and long­term stability. It is useful in verifying HVAC
systems performance and air ventilation
control.

CO is a colorless, odorless, and tasteless
gas which is slightly lighter than air. It is
highly toxic to humans and animals. Carbon
Monoxide is measured using a long-life
electrochemical sensor.

Maximum indoor air quality CO level per
ASHRAE Residential standards 62-1989 for
living area is under 9ppm. It is necessary to
evacuate employees from enclosed spaces
if the CO concentration exceeds 100ppm per
OSHA exposure limit.

1

FEATURES

• Large LCD display with blue backlight for

use in dark areas

• One touch to display CO² / dew point /

temperature / wet bulb temperature / air
temperature / humidity / CO in sequence

• Designed with NDIR waveguide

technology CO² sensor

• Programmable CO level alarm

• Extended drift compensation on

CO² sensor

• Audible alarm (~ 80db) threshold setting

• Max and Min functions included (TWA
and STEL for CO² only)

• Mini USB to PC download function

for analysis

• 99 points manual recording

• 8000 points auto recording

• Review 99 points manual record

from meter

• Hold function freezes current readings

• Housing designed to help air ventilation

for quick and accurate response.

• Easy to manually calibrate CO² to fresh air

(380-420ppm)

MATERIAL SUPPLIED

This package contains:

• Meter

• 4 AA batteries

• Mini USB cable and software CD

• Operation manual

• Hard carrying case

• 33% calibration salt

• 75% calibration salt

• AC Power Adapter

2

POWER SUPPLY

The meter is powered by either 4 AA
batteries or a DC adaptor (9V/1A output.)

Install the batteries into the battery
compartment on the rear of the instrument.
Verify correct polarity and solid contact.

When an adaptor is used, it will cut off

the power supply from the batteries. The
adaptor can not be used as a battery
charger.

When battery voltage gets low, will
appear on the LCD (Fig. 1.) The CO² sensor

accuracy is compromised under low
batteries, replace with fresh batteries or
connect to an adaptor.

LCD DISPLAY

PRIMARY LCD

SECONDARY
LCD

3

SYMBOLS

Primary LCD Measured and calculated

values

Secondary LCD Real time clock

CO² Carbon dioxide reading
CO Carbon monoxide reading

HOLD Readings are frozen

MIN/MAX Minimum/maximum readings

STEL Short-term exposure limit (15

minutes weighted average)*
TWA Time weighted average
(8 hours)*

Low battery indicator

DP Dew point temperature
TA Air temperature

WBT Wet bulb temperature
%RH Percentage of relative humidity
°C/°F Celsius/Fahrenheit scale
CAL In calibration status

REC In manual/automatic logging

RECALL In manual records recall mode

*CO² Only

KEYPAD

Turns the meter on or off.
Press and hold to enter setup mode
while meter is off.
Press while turning the meter
on to disable auto power off.

Exits setup/recall page. Press and
hold to start automatic logging.

Press to switch display mode.
Press and hold to enter memory
recall mode.

4

KEYPAD CONT.

Freezes the current readings. Selects

unit or increases value in setup.
Cancels data hold function.

Press to manually record the
reading. Selects unit or decreases
value in setup.

Displays MIN, MAX, TWA, STEL

function. Saves and finishes settings
while in sleep mode.

OPERATION

POWER ON/OFF

Press to turn the meter on and off. At
power up, the meter emits a short beep and
begins 30 second warm-up countdown

(Fig. 2), then enters normal mode with

current CO² and real time displays (Fig. 3).

NOTE:

THE REAL TIME DISPLAYS DATE
(YY-MM-DD) AND TIME IN SEQUENCE.

TAKING MEASUREMENT

The meter starts measurements when
powered on and updates readings every
second. In the condition of an operating
environment change, (ex. high to low temp)
it takes 30 seconds for the CO² sensor to
respond and 30 minutes for RH sensor.

NOTE: DO NOT HOLD THE METER IN
CLOSE PROXIMITY TO THE FACE AS
EXHALED BREATH AFFECTS CO² LEVELS.

5

CO² (CARBON DIOXIDE)

Press to switch the mode to CO². CO²
concentration will display in ppm on primary

display (Fig. 4). The lower display shows the

real time clock.

AIR, (DP, WBT, TA ) TEMPERATURES

Press to switch to temperature display

(Fig. 5). In the AQM4, dew point temperature

and wet bulb temperature are also available

by repeated pressing of (Fig 6). The

lower display shows the real time clock.

HUMIDITY

Press to switch to humidity display

(Fig. 7). The lower display shows the real

time clock.

CO (CARBON MONOXIDE)

Press to switch the mode to CO. CO
concentration will display in ppm on primary

display (Fig. 8). The lower display shows the

real time clock.

6

DATA HOLD

In normal display mode, press to freeze

the readings, the "HOLD" icon is displayed

on the left top of the LCD (Fig. 9). All current

readings are kept unchanged. Press
to cycle through all held readings.

While in "HOLD" mode, STEL and TWA will
continue updating every 5 minutes.

BACKLIGHT

The backlight will be activated for 10
seconds by pressing any key.

MIN, MAX, STEL, TWA

This meter allows you to check the minimum

and maximum, STEL and TWA values

calculated since power on. Under normal
mode, press to see the minimum,

maximum, STEL and TWA and real time

sequence. Each press of , displays

MIN, MAX, STEL, TWA in sequence and
returns to current value (Fig 10 - 13). STEL
and TWA values are calculated for CO² only.

If the meter is turned on for less than

15 minutes, the STEL value will be the

weighted average of readings taken since

power on. This is also true for TWA values

displayed prior to 8 hours. It takes at least

5 minutes to calculate STEL and TWA.
The display shows "----" during the first 5

minutes from power on.

7

In the MAX/MIN/STEL/TWA modes, it

shows the corresponding readings on the
main display and the real time clock on the
lower display.

In this mode, press to switch the

displayed parameters (Fig 14).

The displayed sequence in this mode is MIN

MAX STEL TWA. Press key to return to

live readings.

"HOLD", "Manually Record", Record" and
"Recall" functions are all available when
meter is in MIN/MAX/AVG mode.

To clear the MIN/MAX/AVG since power
on, restart the meter or press for more
than 2 seconds to clear previous data and
restart.

NOTE:

TWA & STEL ARE FOR CO2
ONLY. MIN/MAX ARE FOR ALL

PARAMETERS

8

MANUALLY RECORDING

The meter features 99 manual memory
locations.

In normal or hold mode, press key to
record, icon and main display flash for
about 3 seconds. The main display shows
the memory serial number. The AQM4 has

99 locations. (Fig. 15)

Each memory contains all parameters

(CO², CO, TA....%rh), not limited to the

selected parameter on the main display.

If the reading
changes quickly,
press to

freeze the reading

before manually
recording the data.

99 MEMORIES RECALL

In normal or hold mode, press key for
more than 2 seconds until the icon
flashes.

Press or to scroll through the
memory locations. The memory serial

number displays on the main LCD first and

then readings stored in that location.

(Fig. 16 & 17)

9

Press key to switch the display

parameter. (Fig. 18)

The time displayed in memory recall mode is
the recording time of this memory.

To escape the memory recall mode, press
key to leave and return to normal
display.

ALARM

The meter features an audible alarm to give
warnings when CO concentration exceeds
a pre-set limit. (See Pg 12, P20 for setting
alarm threshold.) It emits beeps (Abt. 80dB)
when CO level goes over the set value and
stops only when the readings fall below the
set value. It beeps again when value goes
over the limit.

The meter can automatically record readings
of CO²/CO/TEMPERATURE/RH for extended
environment monitoring. The memory
capacity is 8,000 points. Users can set up

sampling rate from 1 second to 4 hours, 59
minutes and 59 seconds. (See pg 11, P40)

After sampling rate is selected, press
for 2 seconds under normal mode to start
logging. The icon flashes to indicate

the logging status and LCD main display

shows the real time CO² measured value.

Lower display is the real time clock. (Fig. 19)

10

To terminate data logging, press for
2 seconds, until icon stops flashing.

NOTE:

The AQM4 will only record one session. If
is activated all previous data is erased.
Download logged data prior to starting
another session.

AUTO POWER OFF

The meter turns off automatically after
20 minutes of inactivity. To override the
function, hold down and for
2 seconds to turn on the meter until "n"
appears. (Fig. 20)

NOTE:

AUTO SLEEP
FUNCTION WILL BE
DISABLED DURING
CALIBRATION MODE

SETUP

When the meter is off,

hold down for
more than 1 second to

enter setup mode. (Fig

21) To exit setup, press
to return
to normal mode.

11

Press or to scroll through set-up
options from the following:
P10 - 99 Memory Clear
P20 - CO Alarm
P30 - Temperature Units

P40 - Logging Sample Rate
P50 - Pressure Compensation

P60 - Real Time Clock

P10: 99 MEMORIES CLEAR

P10 and "CLR" (Fig. 21) are displayed on the
LCD, press to enter into P11 and clear

or keep all the manual records. The current

setting will be blinking on the LCD. (Fig. 22)

Press or to choose NO or YES

and press to confirm.

-OR- Press to escape and return to P10

P20: CO ALARM

When P20 and "ALAR" (Fig. 23) are
displayed on LCD, press to enter into

P21 for setting CO alarm threshold. The

current set value will be blinking on the LCD
(Fig 24). Press to increase or

to decrease the value. The selectable alarm

limits are 25~200ppm in 5 ppm increments.
When the preferred alarm value is set, press

to save the setting

-OR- Press without saving and return
to P20.

12

P30 TEMPERATURE UNIT

When P30 and "UNIT" (Fig 25) are displayed
on the LCD, press to go into P31 to

choose the temperature unit.

The set value will display on LCD (Fig 26)

Press or to choose C° or F° and

press to confirm.

-OR- Press to escape and return to
P30.

P40: LOGGING SAMPLING RATE

P40 allows you to set sampling rate of data

logging (Fig. 27). The range is from 1 second
to 4 hours 59 minutes and 59 seconds.

Press to display current setting and
enter edit mode. The display is in the
format [HH. MM. SS.] The hour digits will
be flashing. To change intervals between
logged readings, press to increase and
to decrease. Press again to
confirm and enter minute setting. Press
to confirm and enter seconds setting.

(Fig 28) Press to confirm the rate

setting.

-OR- Press to escape and return to
P40.

13

P50 PRESSURE COMPENSATION

When P50 and "PRES" (Fig. 29) are displayed
on the LCD, press to set pressure

compensation value for CO² measurement.

The current set will flash on LCD. (Fig. 30)

The barometric pressure unit is kPa.

Press to increase or to decrease
barometric pressure.

-OR- Press to escape and return to P50.

NOTE: ONLY ENTER THIS MODE IF CURRENT
BAROMETER PRESSURE IS KNOWN. MULTIPLY IN.

Hg BY 3.39 TO OBTAIN kPa VALUE.

P60: REAL TIME CLOCK

Enter P60 for setting the real time clock of
this meter. Press to enter into P61 to set
the time format as 12 hour or 24 hour. The

current set will flash on LCD. Press

or to change the format and press
to confirm and continue to set the date

and time. (Fig 32)

-OR- Press to escape and return to P60.

NOTE: DATE FORMAT IS YY:MM:DD.

The date will show on the lower display with
year digits blinking. Press to increase or
to decrease digits. Press to
confirm and continue to next setting. Repeat
above steps to complete the year/month/day/

hour/minute/second setting. (Fig. 32)

14

CALIBRATION MODE

The AQM4 allows you to calibrate CO² and
RH, for CO calibration please send unit to
UEi. To enter calibration mode, place unit
at suitable calibration site specified in the
following sections.
Press + , then also
simultaneously for 3 seconds to turn on the

meter and enter calibration mode (Fig. 33).

Press or to select parameter to
calibrate. To cancel or exit calibration at any
time, turn meter off.

NOTE:

ENSURE THE BATTERIES ARE AT FULL VOLTAGE
BEFORE THE CALIBRATION TO PREVENT
INTERRUPTION OR FAILED CALIBRATION.

CO² CALIBRATION

The manual calibration is suggested to
be done in sunny outdoor air that is well
ventilated. To begin, enter calibration mode.
Press or to select parameters
for calibration and press enter. The meter
is calibrated at standard 400ppm CO²
concentration at the factory. It is suggested
to manually calibrate regularly to maintain
good accuracy.

NOTE:

WHEN THE ACCURACY BECOMES A CONCERN,
RETURN TO UEi FOR STANDARD CALIBRATION.

CAUTION:
Do not calibrate the meter in the air with
unknown CO² concentration. It could be
calibrated as 400ppm by default which
leads to inaccurate measurements.

Wait 10 minutes until the blinking stops and

the calibration is completed. To cancel the
calibration, turn off the meter at any time.

15

RH CALIBRATION

To begin, enter calibration mode. Press
or to select parameters for calibration
and press enter.
The meters default for calibration of

humidity is 33% and 75% salt solution. The
ambient condition is recommended at 70 ~
75°F (25°C) and stable humidity. To cancel

calibration, turn off the meter.

CAUTION:
Do not calibrate the humidity without
default calibration salts. Contact UEi for
calibration salt or for service

33% Calibration

Plug the sensor probe into 33% salt bottle.
Hold down to enter 33% calibration.
"CAL" and calibrating value (32.8% if at
77°F) are blinking on the LCD.

75% Calibration

Plug sensor probe into 75% salt bottle and

enter calibration mode. In calibration mode,

press to select 75% calibration (Fig. 35),

press to start. "CAL" calibrating value

(75.3% if at 77°F) will blink on the LCD.

Meter will begin calibration and finish in
60 minutes when "CAL" and humidity stop
blinking. To cancel the calibration, turn off
the meter at any time.

16

CO CALIBRATION

When the accuracy becomes a concern,

return to UEi for standard calibration. It
is necessary to have standard CO gas for
calibration.

CAUTION:

Do not calibrate the meter in the air with
unknown CO concentration. It could be
calibrated as 400ppm by default which
leads to inaccurate measurements.

TROUBLESHOOTING

Will Not Power On

- Press for more than 3 seconds.

- Check that the adaptor is connected
and on.

- Check that battery level is sufficient
and properly installed.

Readings Not Changing

- Check whether data hold function is
activated (HOLD icon is at the left top).

Slow Response

- Check the air flow channels on
the rear. Verify no blockage exists.

Error Messages

EO1/E33: CO² sensor is out of order. Try new
battery first.
E02: The value is under range.
E03: The value is over range
E04: The original data error results in

this error (DP, WB)

17

Error Messages Cont.

E11: Retry humidity calibration
E16: Retry CO calibration
E31: Temperature sensor AD damaged
E32: Memory IC damaged.
E33: Humidity sensor or circuit
damaged.

PC CONNECTION

The UEi AQM4 can be connected to a PC to
download recorded data.

Plug the USB cable into the socket at the
right side of the meter and the other port to
your PC. Next, install the software on your
PC following these procedures.

1. Insert the CD ROM and run installation.
Select a preferred directory and click
"Next" step by step to finish.

2. After the software installation is
completed, it will run USB driver
installation next.

18

AUTO CONNECT

Start the software and it will detect the
logger connection automatically, indicating
the COM port information at the bottom of
the main screen as well as the COM Port
setting column.

LOGGER SETTINGS

To set up logging plan, click "Setting" icon

and select "Logger". The setting page is

opened.

Users can set up the logger identifier
number. Click OK for setting and exit the
screen to confirm the settings.

19

DATA TRANSMISSION

To transmit auto recorded data from the
meter, click "Download" icon on the left top
side of the main screen. All auto-recorded
data in the logger will be transmitted. The
raw data with time stamp will display at
the lower part of the screen and the graph
in the middle.

In the Graph display, the Y-axis indicates
Temperature, RH, DP,WBT, CO2, and CO

levels in different line colors. The X-axis
can be switched to show Time or Recorded
Number Stamp.

20

VIEW MENU

The following functions help to view the
GRAPH data in more detailed way.

In the view menu, there are 4 tools to
enlarge the Graph data for detailed data
review.

Zoom in: Hold down "Ctrl" key on the PC
keyboard and left click any target point on

the graph to zoom in. Right click at any point
to zoom out.

Zoom Window: Hold down "Ctrl" key and
drag click the left button of the mouse to
select an area on the Graph and the selected
area will be enlarged.

Zoom X-Axis: Hold down "Ctrl" key and
drag click the left button of the mouse to
select an area on the Graph and the X-axis
of the selected area will be enlarged.

Zoom Y-Axis: Hold down "Ctrl" key and
drag click the left button of the mouse to

select an area on the Graph and the Y-axis

of the selected area will be enlarged.

Three icons on the right top side of the main
screen:

Redraw Button: After any review and

zooming on the Graph, click "Redraw" to

reset it to original format.

Clear Button: Click "Clear" to delete all data
and Graph on the window. A warning box

shows up for confirmation. Press "Yes" and

all data will be cleared from the PC.

21

Cursor Button: Switch cursor ON and it
shows the raw data with the cursor. Click
anywhere on the graph and the digital data

will be displayed. Switch OFF to disable the

function.

DATA PROCESSING
The downloaded data can be Saved or
Printed via "File" processing function.

Load: To retrieve saved files, just click

"Load" and select a desired file and it will
be loaded in the main screen with the file
details at the left top side.

22

SPECIFICATION

Measuring Range

CO

²

CO 0 ~ 1000ppm

Temperature -20 ~ 60˚C

Relative Humidity 0.1% ~ 99.9%

Dew Point Temp. -20.0 ~ 59.9˚C

Wet Bulb Temp -5.0 ~ 59.9˚C

Resolution 1ppm, 0.1˚C/˚F, 0.1%RH

Accuracy

CO

²

CO ±10ppm for less than

Temperature ±0.6˚C/+0/9˚F

Relative Humidity ±3% (at 25˚C, 10~90%)

Response Time

CO

²

CO <60 seconds

Tair <2 mins

Relative Humidity <10 mins

LCD/Meter Size (mm) 26(H) x 44 (L),

Operating Condition -20 to 50˚C (CO² Sensor)

Storage Condition -20 ~ 60˚C, 10 ~ 90% RH

Power Supply AA x 4pcs or 9V Adaptor

Battery Life >24 hours

Weight

0 ~ 9999ppm

-5 ~ 140˚F

±30ppm ± 5% of
reading (0 ~ 5000ppm)

100ppm

±10% of reading for
101~500ppm
±20% of reading for 501ppm

and above

±5% (at 25˚C, other range)

<30 seconds

(90% step change)

(90% step change)

(90% step change)

(90% step change)

205(L) x 70 (W) x 56(H)

0 to 500˚C (CO Sensor)

-20 to 60˚C

(Alkaline Battery)

200g

23

CO² LEVELS AND GUIDELINES

REGULATORY EXPOSURE LIMIT

ASHRAE Standard 62.1-2004:

CO² concentration in occupied building
should not exceed 1000ppm.

Building Bulletin 101 (BB101): 1500ppm

UK standards for schools state that CO²
averaged over the whole day (i.e. 9am to

3:30pm) should not exceed 1500ppm.

OSHA: 5000ppm

Time weighted average over five 8-hour

work days should not exceed 5000ppm.

Mak: Germany, Japan, Australia, UK:

5000ppm

Eight hours weighted average in

occupational exposure limit is 5000ppm.

(See Ashrae 62.1-2004 Table B-1)

NON-ENFORCED REFERENCE LEVELS

NIOSH Recommends
250-350ppm: normal outdoor ambient

concentrations

600ppm: minimal air quality complaints

600 - 1000ppm: less clearly interpreted

1000ppm: indicates inadequate ventilation;

complaints such as headaches, fatigue, eye/
throat irritation will be more widespread.
1000ppm should be used as an maximum
limit for indoor levels.

24

CO LEVELS

ppm Symptoms and Applicable Standards

Normal background levels

0-1

Maximum indoor air quality level:

9

Maximum allowable concentration
per ASHRAE Residential Standards
62-1989 for living area.

Maximum limit 8 hours of continuous

25

exposure per California OSHA
workplace standards

Maximum 8 hours average exposure

35

level per US OSHA workplace
standards

Maximum concentration for

50

continuous exposure for any 8 hours
average level per OSHA standards

Evacuate employees from continuous

100

exposure in any 8 hour average level
per OSHA standards.

Mild headache, fatigue, nausea, and

200

dizziness within 2-3 hours

Frontal headache, life threatening

400

after 3 hours. Maximum
concentration in flue gas per the US
EPA and AGA standards

Dizziness, nausea, convulsions, death

800

within 2-3 hours

Nausea within 20 minutes, death

1600

within 2-3 hours.

25

CE CERTIFICATE

The product complies with EMC directive 2004/108/EC
Technical standard: Emission EN 61326-1:2006 Class B
EN 55011:2009/A1:2010 Group 1 Class B
Immunity EN 61326-1:2006 EN 61000-4-2:2009
EN 61000-4-3:2006 A2:2010

26

LIMITED WARRANTY

The AQM4 is warranted to be free from defects
in materials and workmanship for a period of two
years from the date of purchase. If within the
warranty period your instrument should become
inoperative from such defects, the unit will be
repaired or replaced at UEi’s option. This warranty
covers normal use and does not cover damage
which occurs in shipment or failure which results
from alteration, tampering, accident, misuse,
abuse, neglect or improper maintenance. Batteries
and consequential damage resulting from failed
batteries are not covered by warranty.

Any implied warranties, including but not limited
to implied warranties of merchantability and
fitness for a particular purpose, are limited to the
express warranty. UEi shall not be liable for loss
of use of the instrument or other incidental or
consequential damages, expenses, or economic
loss, or for any claim or claims for such damage,
expenses or economic loss. A purchase receipt
or other proof of original purchase date will be
required before warranty repairs will be rendered.
Instruments out of warranty will be repaired (when
repairable) for a service charge. Return the unit
postage paid and insured to:

www.ueitest.com • Email: [e-mail]

8030 SW Nimbus Avenue.

Beaverton, OR 97008

1-800-547-5740 • FAX: [phone]

Claims are not acceptable for improper use
(including adaptation) to particular applications
not foreseen in the instruction manual or improper
combination with incompatible accessories or

equipment, or for repair carried out by unauthorized

personnel.

This warranty gives you specific legal rights. You

may also have other rights which vary from state
to state.

27