MAINTENANCE & TROUBLESHOOTING
5-
1
NOTE
: The monitor draws power from the battery pack even
when turned off. Severe damage to the circuit board may occur
if the battery pack is not disconnected before servicing the unit
or replacing sensors or any other components inside.
4.3. External
Filter
The external filter is made of PTFE (Teflon
®
) membrane with a
0.2 micron pore size to prevent water and dust from being
sucked into the sensor manifold, and to prolong the operating
life of the sensors and pump. The external filter should be
replaced if it changes color, traps dust or other particulates, or
if water has been sucked into it.
For faster response, the user may consider removing the
external filter for some reactive gases including Cl
2
, PH
3
, NH
3
,
and HCN. However, doing so may shorten the pump and
sensor lives.
5.
Troubleshooting Tips
To aid diagnosis of the monitor, it has a diagnostic mode that
displays critical, low level parameters. Section 5.1 describes
the diagnostic mode. Section 5.2 summarizes the frequently
encountered problems and suggested solutions.
Turning the Q-RAE Plus monitor on in diagnostic mode, and
using the troubleshooting table in section 5.2, the user can
narrow problems down to one or two areas and often correct
the problem without having to return the monitor for repair.
WARNING!
The diagnostic mode allows the user to set several low-
level parameters that are critical to monitor operation.
Extra care should be taken when setting these low-level
parameters. If the user is not familiar with these
parameters and sets them incorrectly, it may cause the
monitor to malfunction.
