LTV 1150 - Page 86

Page 7-8 LTV
®
1200/1150 Ventilator Service Manual p/n 18603-001, Rev. C
Symptoms Possible Causes What to Do
Very small ET tube
connected directly to wye.
A very small ET tube connected directly to
the wye may cause turbulence that causes
the flow differential to be read incorrectly.
To reduce this turbulence, add a short
larger bore extension between the ET tube
and wye. In this case, the monitored
volume is high, but the delivered volume is
accurate.
Low side sense line or
elbow at patient wye loose
or leaking.
High or low sense lines are
occluded.
High or low sense ports in
the wye are occluded.
Check high and low pressure sense lines
to be sure they are correctly attached and
securely seated at both the ventilator and
wye ends.
Check the Luer fitting connections for
leaks.
Check the elbow connectors at the wye to
be sure they have not loosened or been
broken loose.
Verify lines are not occluded or pinched.
Sense lines are reversed. The sense lines are not designed to be
removed from either the wye or the Luer
fittings. If the sense lines have been
removed and replaced incorrectly, they
may not seal correctly when replaced.
Replace the patient wye and sense lines
with a known good assembly.
Failed auto zero.
Perform an auto zero under XDCR ZERO
.
See the LTV
®
1200 or the LTV
®
1150
Ventilator Operator's Manual for more
information.
VHome setting does not
match flow valve.
Correct the VHome setting. See Chapter 6
- Maintenance & Calibration.
Bypass flexible tube
pinched.
Pinhole leaks in bypass
flexible tube.
If the bypass flexible tube is pinched, it
can usually be seen pressed against the
louver openings in the bottom of the
ventilator case.
Open the ventilator and remove the back
panel. Replace the back panel being sure
to fit the louvers in between the upper and
lower loop of the bypass flexible tube
before seating the back cover.
If the bypass flexible tube is leaking,
replace it.
Monitored volume is
high.
Delivered volume is
high.
Failed calibration. Recalibrate the vent. See Chapter 6 -
Maintenance & Calibration for instructions.
If the problem reoccurs after careful
recalibration, a transducer may be drifting
excessively. Perform the Advanced Vte
Diagnostic Procedures, see page 7-23.