User's Manual

AirMeter
TM
Test Tool
Taking Measurements
11
4. Press  and  as necessary to change the
item values. Hold down  or  to increase the
rate of change.
5. Press  [Select], or in some cases [Done], to
store the changes.
6. Press  for 2 seconds to exit the Setup menu. All
changes are stored.
Taking Measurements
The Meter measures:
• Temperature, Dew Point, and Wet Bulb
• Relative Humidity (%RH)
• Carbon monoxide (CO) levels
• Carbon dioxide (CO
2
) levels
• % Outside Air
• Air Velocity (standard and actual)
• Flow Rate
Temperature, Relative Humidity, CO, CO
2
, Dew
Point, and Wet Bulb Measurements
When the Meter completes and passes its self-test, it is
ready to take temperature, relative humidity, CO, CO
2
,
dew point, and wet bulb readings. If the Meter is
displaying another function menu, press
.
Temperature, relative humidity, CO, and CO
2
readings
are shown on this screen.
• Dew point is the temperature at which condensation
starts. To view the dew point from the main menu,
press  [Dew Point]. The dew point reading
appears on the top right of the display.
• Wet bulb temperature is the lowest temperature that
evaporating water can reach. To view the wet bulb
temperature from the main menu, press  [Wet
Bulb] (or  [Wet Bulb] if the Meter is displaying
dew point temperature). The wet bulb reading
appears on the top right of the display.
From either the wet bulb or dew point screens, press
 [Main] to return to the main screen.
% Outside Air
Air conditioning systems rely on outside air, mixed air,
and return air to help cool, heat, or purify their output. A
balance of the three is also a factor in achieving optimum-
energy usage from the conditioning unit.
The Meter’s Percentage (%) Outside Air function
computes the percentage of outside air two different
ways, either by measuring temperature or by measuring
CO
2
content.
The formula for calculating % outside air is:
% Outside Air = (Return Air – Mixed Air) x 100 %
Return Air – Outside Air
Determining the % outside air requires entering values for
return air, outside air, and mixed air into the formula.
These values can be in temperature or CO
2
content. The
values can be measured with the Meter or, in the case of
outside air, can also be entered manually. Once the