Mindray WATO EX-55, Service Manual

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5.3.5 Tidal Volume
The following table lists tidal volume inaccuracy related failures.
Failure
description
Possible cause Recommended action
The flow sensor is not installed
properly. Re-install the flow sensor.
The setting of fresh gas flow is
inappropriate. Adjust the fresh gas flow.
There are significant leaks in the
breathing system and the fresh
gas flow is too low. Repair the leaking points after checking as
per the procedures described in sections
5.3.3Anesthetic Gas Delivery System
and
5.3.4Patient Circuit
.
* There is water build-up inside
the flow sensor. Remove the flow sensor and clear its inside
water build-up.
*The membrane of the flow
sensor assembly is distorted,
dirty or its inside resistance
changes. Zero drift occurs to the
pressure sensor on the monitor
board. Enter the user maintenance mode and
calibrate the flow sensor as per section
4.3.2Flow Calibration (factory)
.
*The flow sensor pressure
sampling pipeline is leaky. Repair the leaking points after checking as
per the procedures described in section
5.3.4.1Leak Test of Flow Sensor Pressure
Sampling Pipeline
.
*The flow sensor is damaged. Replace the flow sensor.
*The pressure sensor on the
monitor board is faulty. Replace the monitor board.
The inlet gas flow regulator on
the integrated pneumatic circuit
of the expiratory valve assembly
is faulty. Replace the integrated pneumatic circuit of
the expiratory valve assembly or replace the
expiratory valve assembly.
Inaccurate tidal
volume
The current Plimit is set too low,
which causes expiration to start
in advance. Set Plimit to a higher value to cause Paw
not to exceed the limit.