Gas Sampling System Troubleshooting; Sampling System Leak Test - GE B30 Technical Reference Manual

Problem
no response to breathing
ETCO over scale >20%
2
Shown until 32%,
specified range 0...20%
ETCO >PaCO
2 2

7.3 Gas sampling system troubleshooting

The faults which can occur in the sampling system are: leaks or blockages in the tubing, failure
of the sampling pump or the magnetic valves, or diminishing of the flow rates because of dirt
accumulating in the internal tubing.
The following checks should help in localizing the fault. Whenever suspecting the sampling
system and always after having done any work on the sampling system, check and if
necessary adjust the flow rate.
CAUTION The special internal sample tube is mechanically fragile. Sharp bends will
cause leaks.
NOTE: D-fend water trap should be replaced, when the 'REPLACE D-FEND' message appears
during the monitor startup.
NOTE: If any liquid has entered the miniC measuring unit due to water trap filter failure, leave
the module running without a sampling line for several hours and check the functions after it
has dried out.

7.3.1 Sampling system leak test

1. Connect a flow cassette with a high flow resistance value (50/1.1) to the end of the
sampling line and start following the 'Amb-Work' value in the service menu. When the
value exceeds 130 mmHg, connect the other port of the flow cassette to the sample gas
out connector and switch off the pump.
2. Wait until the pressure inside the sampling system is stabilized, then observe the shown
Amb-Work value. The value, i.e. the pressure inside the sampling system, should not drop
more than 6 mmHg in 20 seconds.
3. If the pressure drops more, first ensure the connections you have made and repeat the
test.
Cause
•
apnea
•
(disconnection)
•
sampling line or water trap loose or
blocked (air leak)
•
sample gas outlet blocked
•
abnormally high ETCO
hypercapnia)
•
CO sensor contaminated
2
•
D-fend malfunction
•
unit is mmHg or kPa and ETCO
to arterial PCO
2
•
"dry gas" as default
What to do
•
check all connections
•
check that outlet is open
•
(permissive let the module run without a
2
sampling line until the CO
sensor has dried out
•
change D-fend
•
is close change to "wet gas" by using
2
install/service menu
Troubleshooting
2
8-31
Document no. 2044677-001