Ventilators · LTV family

Pulmonetic Systems LTV 1000: troubleshooting and error codes

The ServiceForge knowledge base holds 141 documented symptoms for the Pulmonetic Systems LTV 1000, with 350 ranked causes, 165 diagnostic checks with test points and expected values, and 100 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Monitored volume is low with delivered volume low

Both monitored and delivered volumes are reading lower than expected

Ranked causes

1. Sense lines are reversed (occasional)
2. Leak Compensation is not on (common)
3. Failed auto zero (common)
4. VHome setting does not match flow valve (occasional)
5. Bypass flexible tube pinched or leaking (occasional)
6. Failed calibration (common)
7. Defective flow valve (occasional)
8. Defective turbine (occasional)
9. Circuit leak (occasional)
10. High or low side sense line or elbow at patient wye loose or leaking (common)
11. Exhalation drive line leaking or loose (common)

11 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated DISC/SENSE alarms patient safety

Disconnect or sense pressure alarms recur during normal operation; may include exhalation valve or pressure sensing faults

Ranked causes

1. Circuit disconnected from patient, wye or vent (common)
2. Exhalation valve disconnected from wye (common)
3. PEEP valve or peepless cap disconnected from wye (common)
4. High or low side sense lines disconnected or inappropriately attached (common)
5. High or low sense line or elbow at patient wye loose or leaking (occasional)
6. High or low sense lines are occluded (occasional)
7. High or low sense ports in the wye are occluded (occasional)
8. Exhalation drive line leaking or loose (occasional)
9. Defective transducer on analog board (occasional)
10. Defective auto zero solenoid (occasional)

First check

Visually inspect all circuit connections at patient interface

Test point: Circuit, wye, exhalation valve, PEEP valve connections
Expected: All connections secure and intact; no visible disconnections

2 more checks with pass and fail actions, 10 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Delivered pressure is high patient safety

Ventilator output pressure exceeds expected levels during operation

Ranked causes

1. Pressure sensing line issue (common)
2. Sense lines occluded (occasional)
3. High or low sense ports in wye occluded (occasional)
4. Failed auto zero (occasional)
5. VHome setting does not match flow valve (occasional)
6. Failed calibration or analog board defective (occasional)
7. Internal flexible tubing issues (occasional)
8. Defective flow valve (occasional)
9. Defective turbine (rare)

7 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator is auto cycling patient safety

Ventilator cycles or triggers breaths without patient effort

Ranked causes

1. Circuit leak (common)
2. High or low side sense line or elbow at patient wye loose or leaking (common)
3. High or low sense lines are occluded (occasional)
4. High or low sense ports in wye are occluded (occasional)
5. Bypass flexible tube pinched (occasional)
6. Pinhole leaks in bypass flexible tube (occasional)
7. Pressure Control or Pressure Support set below PEEP (occasional)
8. Failed auto zero (occasional)
9. Failed calibration (occasional)

10 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Monitored pressure is low

System pressure transducer reading below expected levels

Ranked causes

1. Pressure sensing line or port issue (common)
2. High or low sense lines occluded (occasional)
3. High or low sense ports in wye occluded (occasional)
4. Failed auto zero (occasional)
5. VHome setting does not match flow valve (occasional)
6. Failed calibration or transducer drift (occasional)
7. Defective flow valve (occasional)
8. Defective turbine (rare)

8 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

O2% is high patient safety

Delivered oxygen percentage exceeds prescribed FIO2 level (LTV 1000 only)

Ranked causes

1. O2 inlet pressure too high (common)
2. O2 inlet flow too high (common)
3. Low O2 Source incorrectly selected (occasional)
4. Flow valve output is low (occasional)
5. Failed calibration or analog board defective (occasional)
6. Internal flexible tubing issues (occasional)
7. Defective or leaking solenoid manifold (rare)
8. Incorrect O2 blender solenoid output flow (rare)

8 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

O2% is low patient safety

Delivered oxygen percentage below prescribed FIO2 level (LTV 1000 only)

Ranked causes

1. O2 inlet flow too low (common)
2. Rolled or leaking flow valve inlet gasket (occasional)
3. Flow valve output is high (occasional)
4. Failed calibration or analog board defective (occasional)
5. Internal flexible tubing issues (occasional)
6. Defective or leaking solenoid manifold (rare)
7. Incorrect O2 blender solenoid output flow (rare)

7 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

PEEP low or sags during exhalation patient safety

Monitored PEEP drops over long exhalation or does not hold steady pressure

Ranked causes

1. Circuit leak (common)
2. PEEP spring not installed in exhalation valve (occasional)
3. Diaphragm incorrectly seated or installed backwards in exhalation valve (occasional)
4. Worn PEEP spring (occasional)
5. High side sense line or elbow at patient wye loose or leaking (common)
6. Failed calibration (occasional)
7. Defective analog board (rare)

First check

View monitored PEEP using RT XDCR DATA display

Test point: RT XDCR DATA
Expected: Monitored PEEP matches actual PEEP

8 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator does not operate from external power

Unit fails to run when connected to AC adapter power source

Ranked causes

1. Defective AC source (common)
2. AC adapter power cord loose (common)
3. Defective AC adapter (occasional)
4. Defective power board (occasional)
5. Internal battery depleted (common)
6. Internal battery not connected (occasional)
7. Defective internal battery (occasional)

First check

Verify AC adapter is plugged into good AC source

Test point: AC power outlet
Expected: AC power available

1 more check with pass and fail actions, 7 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Monitored volume is high with delivered volume high

Both monitored and delivered volumes are reading higher than expected

Ranked causes

1. Very small ET tube connected directly to wye (rare)
2. Failed calibration (common)
3. Defective flow valve (occasional)
4. Defective turbine (occasional)
5. Defective or leaking solenoid manifold (occasional)
6. Circuit leak (occasional)

6 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Vent Inop LED is on and ventilator not ventilating patient safety

Ventilator powers on but Vent Inop LED illuminates and no ventilation occurs

Ranked causes

1. Ventilator ran on internal battery and battery became depleted (common)
2. Event trace shows reason for inop condition (common)
3. Memory board JP3 connector jumper not installed or mispositioned (occasional)
4. Defective memory board (occasional)
5. Defective power board (occasional)
6. Defective main board (rare)

First check

Verify external power connection

Test point: AC power source and adapter
Expected: Ventilator connected to external power

1 more check with pass and fail actions, 6 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Delivered pressure is low with PEEP low and ventilator auto cycling patient safety

Delivered pressure is low, PEEP is low, and ventilator is auto cycling abnormally

Ranked causes

1. Leak Compensation is not on (common)
2. Sense lines are reversed (occasional)
3. High or low sense lines are occluded or at wye loose or leaking (common)
4. Exhalation drive line leaking or loose (common)
5. Exhalation valve leaking during inspiration (occasional)

5 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Power-on self-test failure patient safety

POST messages (CPU, SRAM, INT VECTOR, ROM CRC, EEPROM) do not complete or ventilation does not begin within 20 seconds of power-on

Ranked causes

1. CPU failure or malfunction (unknown)
2. SRAM failure or malfunction (unknown)
3. INT VECTOR failure (unknown)
4. ROM CRC error (unknown)
5. EEPROM failure or malfunction (unknown)

5 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated DISC/SENSE alarms with XDCR FAULT also occurring patient safety

Combination of disconnect/sense and transducer fault alarms occurring repeatedly

Ranked causes

1. Pressure Control or Pressure Support set below PEEP (common)
2. Internal flexible tubing occluded or pinched (occasional)
3. Internal flexible tubing has pinhole leaks or leaking at connections (occasional)
4. Defective transducer on analog board (occasional)
5. Defective auto zero solenoid (occasional)

First check

Verify Pressure Control and Pressure Support settings

Test point: Ventilator control panel settings display
Expected: PC and PS values set at or above PEEP value

1 more check with pass and fail actions, 5 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator does not power on

Unit fails to power up or turn on when power button is pressed

Ranked causes

1. Defective AC source, adapter, or depleted internal battery (common)
2. Memory board JP3 connector jumper not installed or mispositioned (common)
3. Defective memory board (occasional)
4. Defective power board (occasional)
5. Defective main board (rare)

First check

Verify external AC power connection

Test point: AC adapter connection
Expected: Power cord fully seated to adapter and wall outlet

2 more checks with pass and fail actions, 5 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator will not exhale, repeated HIGH PRES alarms patient safety

Ventilator stuck in inspiration with continuously rising pressure; exhalation function fails; turbine stops and auto-cycles to HIGH PRES

Ranked causes

1. Diaphragm installed backwards or incorrectly seated in exhalation valve (common)
2. Sense lines occluded, pinched or reversed (common)
3. Internal flexible tubing occluded or pinched (occasional)
4. Internal flexible tubing has pinhole leaks or leaking at connections (occasional)
5. Defective exhalation drive solenoid (occasional)

First check

Visually inspect exhalation valve diaphragm orientation

Test point: Exhalation valve interior
Expected: Diaphragm and spring correctly seated per Chapter 4 diagram

1 more check with pass and fail actions, 5 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Alarm does not sound during ALARM test

No audible alarm during alarm test checkout

Ranked causes

1. Defective power board (common)
2. Ventilator does not have power board P/N 15000 installed (occasional)
3. Audible alarm did not sound long enough before test termination (occasional)
4. Alarm sounder disconnected (occasional)

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Delivered flow is high patient safety

Ventilator delivering higher than prescribed tidal or minute volume

Ranked causes

1. Circuit leak (common)
2. Sense lines reversed (occasional)
3. Pressure sense line or port issue (common)
4. Control settings incorrect (common)

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Delivered flow is low patient safety

Ventilator delivering lower than prescribed tidal or minute volume

Ranked causes

1. Failed auto zero (common)
2. Leak Compensation not enabled (common)
3. Bypass flexible tube issues (occasional)
4. Failed calibration or transducer drift (occasional)

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Exhalation valve leaking during inspiration patient safety

Exhalation valve allows gas to escape to atmosphere during inspiratory phase instead of maintaining pressure

Ranked causes

1. Diaphragm installed incorrectly or spring misseated (common)
2. Exhalation diaphragm worn or defective (occasional)
3. PEEP spring worn or defective (occasional)
4. Exhalation valve body defective or damaged (occasional)

First check

Verify diaphragm and spring correct orientation and seating

Test point: Exhalation valve interior
Expected: Diaphragm and spring seated per Chapter 4 diagram; no gaps

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Leak test fails

Leak test checkout fails

Ranked causes

1. Circuit connections or accessories are leaking (common)
2. Internal flexible tubing occluded, pinched, or leaking (common)
3. Over pressure relief valve, subambient relief valve, or flow valve leaking (common)
4. VHome setting does not match flow valve (occasional)

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated RESET alarms with CRC, STACK, POST, or RUNAWAY event log

RESET alarm recurs; Event Log shows CRC, STACK, POST, or RUNAWAY error codes

Ranked causes

1. Electrostatic discharge (ESD) (occasional)
2. Defective memory board (common)
3. Defective main board (common)
4. All other causes (rare)

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated XDCR FAULT alarms

Transducer fault alarms occur repeatedly; pressure measurement or sensing circuitry failure

Ranked causes

1. Internal flexible tubing occluded or pinched (common)
2. Internal flexible tubing has pinhole leaks or leaking at connections (common)
3. Defective transducer on analog board (occasional)
4. Defective auto zero solenoid (occasional)

First check

Inspect internal flexible tubing for occlusions and kinks

Test point: Solenoid manifold and analog board tubing connections
Expected: All tubing clear of obstructions and not pinched

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Sensitivity does not appear to be accurate patient safety

Ventilator trigger sensitivity setting does not match actual sensitivity response

Ranked causes

1. High or low sense lines occluded (occasional)
2. High or low sense ports in wye occluded (occasional)
3. Condensation in sense lines (occasional)
4. Failed calibration (occasional)

5 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator does not operate from internal battery

Unit fails to run when on battery power or shuts off when external power removed

Ranked causes

1. Internal battery depleted (common)
2. Internal battery not connected (occasional)
3. Defective internal battery (occasional)
4. Defective power board (occasional)

First check

Measure battery runtime at nominal settings

Test point: Ventilator output during battery operation
Expected: Runs for more than 40 minutes at nominal settings

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator is on, gas is not delivered and turbine is running patient safety

Ventilator powered and turbine spinning but no gas output to patient

Ranked causes

1. Defective or disconnected solenoids (occasional)
2. Defective or disconnected flow valve (occasional)
3. Defective turbine (occasional)
4. Defective purge solenoids (rare)

8 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator makes a high pitched noise when in Standby caution

Audible high-pitched sound emitted while ventilator in Standby mode

Ranked causes

1. Battery charge circuit running in bulk charge (common)
2. Defective or disconnected fan (occasional)
3. Defective power board (occasional)
4. Defective thermo conductive heat sink pads (rare)

5 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator won't trigger at sensitivity setting of 1 Lpm patient safety

Ventilator does not initiate breath when patient effort is 1 Lpm or below set sensitivity

Ranked causes

1. Patient effort inadequate (occasional)
2. Failed auto zero (occasional)
3. Leak Compensation is not on (occasional)
4. Failed calibration (occasional)

First check

Perform auto zero calibration

Test point: XDCR ZERO menu
Expected: Auto zero completes without error

1 more check with pass and fail actions, 5 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

A control does not operate

Front panel control is unresponsive or non-functional

Ranked causes

1. Front panel ribbon cable not properly connected (common)
2. Front panel ribbon cable damaged (occasional)
3. Defective switch or main board (occasional)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Alarm does not sound at all patient safety

Audible alarm system completely silent; no alarm sounds for any alarm condition

Ranked causes

1. Ventilator did not run for more than 1 minute (common)
2. Defective or disconnected sounder (occasional)
3. Defective power board (occasional)

First check

Run ventilator for minimum 1 minute

Test point: Ventilator operation
Expected: Unit runs continuously for at least 1 minute

1 more check with pass and fail actions, 4 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Audible alarm too soft during ALARM test

Audible alarm volume is insufficient during alarm test checkout

Ranked causes

1. Alarm volume set too low (common)
2. Alarm sounder blocked (common)
3. Defective alarm sounder (common)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery Charge Status LED is flashing amber

Charge Status LED flashes amber during battery evaluation or charging phase

Ranked causes

1. Internal battery charging normally (common)
2. Defective internal battery (occasional)
3. Defective power board (occasional)

First check

Observe Charge Status LED behavior during charging

Test point: Charge Status LED on ventilator panel
Expected: Flashing amber for up to 1 hour if deeply discharged, then solid amber while charging

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery Charge Status LED is solid red

Charge Status LED displays solid red indicating internal battery disconnection or defect

Ranked causes

1. Internal battery not connected (common)
2. Defective internal battery (occasional)
3. Defective power board (occasional)

First check

Verify internal battery is physically connected

Test point: Internal battery connector inside ventilator
Expected: Battery connector fully seated and secured

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Battery does not reach full charge

Internal battery fails to charge to full capacity or depletes too quickly during use

Ranked causes

1. Internal battery deeply discharged (common)
2. Defective internal battery (occasional)
3. Defective power board (occasional)

First check

Charge battery for extended period if deeply discharged

Test point: Charge Status LED indicator
Expected: Solid amber LED after initial evaluation phase

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Control display flashing when setting a control

Control value display flashes while attempting to adjust a setting

Ranked causes

1. Control setting is limited by other control values (common)
2. Wrong model selected in VENT MTNCE (occasional)
3. LED misalignment (rare)

First check

Identify which controls are flashing

Test point: Display screen during adjustment
Expected: Other controls flash to indicate dependency

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

DEFAULTS alarm with invalid or out-of-range settings

DEFAULTS alarm occurs; some or all control settings were invalid or out of range on power up and were restored to defaults

Ranked causes

1. Electrostatic discharge (ESD) (occasional)
2. Defective main board (common)
3. Defective memory board (common)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display or LED does not illuminate during DISPLAY test

A display or LED fails to illuminate during display test checkout

Ranked causes

1. Misaligned LED (occasional)
2. Defective LED or display (common)
3. Defective main board (common)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

HIGH PRES alarm occurred but did not sound patient safety

High pressure condition detected and displayed but audible alarm did not activate

Ranked causes

1. Alarm silence was already active (common)
2. High pressure alarm delay is on (common)
3. Alarm automatically silenced after 3 seconds (occasional)

First check

Check Silence/Reset LED status

Test point: Silence/Reset LED indicator
Expected: Green or off; not red

1 more check with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Incorrect message displayed when rotary switch turned during CONTROL test

Correct message not displayed when rotary switch is turned, or incorrect message is displayed

Ranked causes

1. Front panel ribbon cable not properly connected (occasional)
2. Front panel ribbon cable damaged (occasional)
3. Defective main board (common)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Oxygen enrichment out of specification patient safety

External oxygen monitor does not read 55% to 65% O2 when O2% control is set to 60% with 0-80 PSIG oxygen supply

Ranked causes

1. Oxygen mixing valve malfunction or blockage (occasional)
2. Oxygen supply pressure out of range (occasional)
3. External oxygen monitor malfunction (occasional)

First check

Connect oxygen supply and set O2% control to 60%

Test point: Ventilator O2% control
Expected: O2% control set to 60

1 more check with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated HW FAULT alarms with delivered pressures and volumes off

Hardware fault alarms occurring with inaccurate pressure and volume delivery; multiple system failures

Ranked causes

1. Flow valve malfunction or disconnection (common)
2. Motor board defective or failed (occasional)
3. Event Log shows SYNC ER1 or HOME ER1 (occasional)

First check

Check Event Trace for SYNC ER1 or HOME ER1 errors

Test point: Event Trace log in ventilator memory
Expected: No SYNC ER1 or HOME ER1 errors present

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated HW FAULT alarms with EEPROM event log

HW FAULT alarm recurs; Event Log shows EEPROM error

Ranked causes

1. Defective power board (common)
2. Electrostatic discharge (ESD) (occasional)
3. Defective main board (common)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Repeated HW FAULT alarms with fan not turning and excessive heat caution

Hardware fault alarm with fan failure; ventilator overheating due to non-functional cooling fan

Ranked causes

1. Defective or disconnected fan (common)
2. Fan housing screws over-tight (occasional)
3. Event Log shows FAN FLT1 (occasional)

First check

Visually observe fan operation through side grill

Test point: Fan grill on side of ventilator case
Expected: Fan blades rotating smoothly at normal speed

2 more checks with pass and fail actions, 6 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator auto cycling with very small monitored volumes patient safety

Ventilator cycles abnormally with low monitored volumes; RT XDCR DATA item shows negative flows during exhalation and positive flows during inspiration

Ranked causes

1. Sense lines are reversed (occasional)
2. Diaphragm installed backwards or incorrectly seated in exhalation valve (occasional)
3. Sense lines occluded, pinched or reversed (common)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ventilator does not work with LTM Graphics Monitor

Ventilator cannot communicate with or operate LTM Graphics Monitor

Ranked causes

1. Communications setting is not set to MONITOR mode (common)
2. Ventilator requires upgrades for LTM compatibility (occasional)
3. Defective connections between LTM Graphics Monitor and ventilator (occasional)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Volume mode operation out of specification patient safety

Exhaled tidal volume, I:E ratio, breath rate, or minute volume readings outside expected ranges during volume assist/control operation

Ranked causes

1. Incorrect ventilator settings (common)
2. Circuit leak or patient disconnect (common)
3. Test lung or patient compliance issue (occasional)

First check

Verify ventilator mode and basic settings are correctly configured

Test point: Ventilator control panel
Expected: Mode: Volume Assist/Ctrl; BPM: 12; Tidal Volume: 500 ml; Insp. Time: 1.0 sec; PEEP: 5 cmH2O; O2%: 21; Sensitivity: 3; High Pressure Limit: 100; Low Pressure alarm: 5; Low Min Vol: 1.0 L

4 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

AP transducer out of tolerance

AP transducer reading variance exceeds acceptable tolerance when tested with applied pressures

Ranked causes

1. Transducer requires recalibration (common)
2. Analog board defective (occasional)

First check

Verify RISE TIME setting

Test point: VENT OP menu
Expected: Profile 5

2 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Audible alarm too soft during Vent Inop Alarm test patient safety

Vent Inop alarm audible tone is too soft during test

Ranked causes

1. Alarm sounder blocked (common)
2. Sounder fails to sound (common)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Bypass Valve suspected faulty patient safety

Tidal volume variance between horizontal and upright positions exceeds 100 mL when measured over 8 consecutive breaths

Ranked causes

1. Leaking or damaged tubing from flow valve to turbine manifold (common)
2. Faulty turbine manifold (occasional)

First check

Measure Vte in horizontal position

Test point: Display
Expected: average of 8 consecutive breaths

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Turbine flow valve

Turbine flow valve accuracy checkout and recalibration of flow output

Ranked causes

1. Flow valve output variance within recalibration range (common)
2. Flow valve defective or out of range (occasional)

First check

Test at 10 Lpm and 4000 RPM

Test point: Calibrated flow meter output
Expected: 9.5 to 10.5 Lpm, 9.5 to 10.5
Tools: Calibrated flow meter

4 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Confirming audible chirp does not sound during Vent Inop Alarm test

No confirming chirp from Vent Inop alarm during test

Ranked causes

1. Audible alarm did not sound long enough before test termination (occasional)
2. Defective power board (common)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Controls are locked

LOCKED message displays when attempting to select or adjust a control

Ranked causes

1. Control Lock button engaged (common)
2. Control Lock button in HARD mode (occasional)

First check

Press Control Lock button

Test point: Control Lock button
Expected: LOCKED message disappears; controls become active

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Date/time/usage meter not incrementing correctly

Date, time, or usage meter does not increment correctly after 1 hour of operation with test lung and power cycle

Ranked causes

1. Real-time clock malfunction or battery depleted (occasional)
2. Usage meter counter circuit malfunction (occasional)

First check

Set ventilator date to current date; note date and format displayed

Test point: Ventilator date setting menu
Expected: Current date set in displayed format

6 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Defective flow valve

Flow valve not calibrated or functioning correctly

Ranked causes

1. Flow valve requires calibration (common)
2. Flow valve defective or failed (occasional)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Delivered and monitored volumes, pressures, and sensitivity are off patient safety

Displayed values for volume, pressure, or sensitivity do not match actual values

Ranked causes

1. Failed calibration (common)
2. VHome setting does not match flow valve (occasional)

First check

Recalibrate ventilator

Test point: Calibration menu
Expected: All values match actual measured values

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Delivered pressure higher than set pressure on test lung

Pressure readings exceed the set value when testing with a test lung

Ranked causes

1. Pressure > 40 cmH2O used on small test lung (Pulmonetic Systems or Siemens 190) (common)
2. Test lung with small aperture connected directly to wye (occasional)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Disc/Sense alarm does not activate patient safety

DISC/SENSE alarm fails to activate when high pressure sense line is disconnected from ventilator

Ranked causes

1. Pressure sense line sensor failure (occasional)
2. Sense line disconnection detection circuit failure (rare)

First check

Disconnect high pressure sense line and observe alarm response on next breath

Test point: Ventilator high pressure sense port, alarm panel
Expected: DISC/SENSE alarm activates on next breath

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display or LED does not illuminate

A display element or LED is dark or non-functional

Ranked causes

1. Defective LED or display element (common)
2. Defective main board (occasional)

First check

Perform display test during startup

Test point: All display elements
Expected: All displays illuminate and respond during test

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Failed calibration

Calibration procedure fails to complete or pressure/flow readings remain inaccurate after recalibration

Ranked causes

1. Calibration procedure incomplete or incorrect (common)
2. Transducer drifting excessively (occasional)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

FDb (Inspired Volume) transducer out of tolerance

FDb transducer reading variance exceeds acceptable tolerance when tested at 30 cmH2O (LTM only)

Ranked causes

1. Transducer requires recalibration (common)
2. Analog board defective (occasional)

First check

Apply 30 cmH2O to Flow Differential transducer low side port

Test point: FDb transducer low side port
Expected: FDb readout within +/- 0.5 cmH2O of 30, +/- 0.5 cmH2O

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

More symptoms

FDw (Monitored Volume) transducer out of tolerance
Flow valve inaccurate
FVd (Delivered Volume) transducer out of tolerance
Hi and Low Flow transducer leak test fails
High pressure alarm does not activate
HW FAULT alarm with AD MMTCH error
Internal inlet filter requires cleaning or replacement
Keypad ribbon cable damage during main board replacement
Low minute volume alarm does not activate
Low O2 pressure alarm does not activate
Low pressure alarm does not activate
Message not displayed when control button pressed during CONTROL test
O2 inlet pressure transducer out of tolerance
O2% display flashing
Over-pressure relief valve exceeds pressure limit
Oxygen transducer calibration error
Patient Assist port resistance out of specification
Power board assembly requires replacement
Power Lost alarm does not activate
Pressure operation monitoring out of specification
Set pressure not reached and turbine humming
Set Value knob does not operate
Vent Inop alarm does not sound continuously
Vent Inop alarm does not sound during Vent Inop Alarm test
Vent Inop alarm tone and/or LED fails test
Ventilator does not reset when Watchdog test performed
Audible alarm too loud during ALARM test
Battery Charge Status LED is flashing red
Bypass flexible tube pinched
Calibration verification after software upgrade
Cannot unlock controls
Configuration settings check after software upgrade
Confirming audible chirp does not sound during ALARM test
Control button name not displayed or incorrect name displayed during CONTROL test
Control is not selected
Control not active in selected mode
Controls are limited
Defective analog board
Defective power board
Defective turbine
Delivered pressure is low
Delivered volume is high
Displays are blanked while on battery power
Failed auto zero
High Pres Limit display flashing
Internal battery pack requires replacement
Internal flexible tubing has pinhole leaks or leaking at connections
Internal flexible tubing occluded or leaking
Internal flexible tubing occluded or pinched
Leak test fails with LEAK --- FAIL message
LED alignment check during board replacement
LED portion of Vent Inop Alarm test fails
Low Min Vol display flashing
Low Pressure display flashing
Main board assembly requires replacement
Main board installation misalignment
Memory board installation with JP3 jumper verification
Monitored pressure is high
Monitored volumes very high on test lung
NO CAL DATA alarm with no calibration displayed
O2 blender label check for software version 5.0 or greater on LTV 1000
O2 blender label replacement for version 5.0 upgrade on LTV 1000
O2 blender solenoid output flows out of specification
O2 Leak Test fails
OPRV test fails
Oxygen transducer leaks
PEEP is low
Pinhole leaks in bypass flexible tube
Power board replacement procedure
Pressure Control display flashing
Pressure Support display flashing
Pressure Support or Pressure Control not functioning properly
Repeated HW FAULT alarms with INTRRPT1 or INTRRPT2 event log
RESET alarm occurs after POST tests
Software version verification after memory board upgrade
Vent in Standby
Vent Inop alarm tone and/or LED fails 15-second duration test
Ventilator gets excessively hot
Ventilator running but displays are turned off
Ventilator will not allow patient to exhale
VHome setting does not match flow valve

81 more symptoms with ranked causes and checks are in ServiceForge. Connect ServiceForge to your AI

Error codes

Code	Meaning	Trigger	Severity
`01`	Power on	Ventilator powered on	info
`02`	Power off	Ventilator powered off	info
`03`	Set hour meter	Operating hours recorded	info
`04`	Set vent check	Entered VENT CHECK mode	info
`05`	Apnea mode entered	Apnea mode activated	warning
`06`	Apnea mode exited	Apnea mode deactivated	info
`08`	High side disconnect	High pressure sensor circuit opened	error
`09`	Low side disconnect	Low pressure sensor circuit opened	error
`10`	Circuit disconnect exited	Disconnect condition resolved	info
`11`	Internal battery empty occurred	Battery charge depleted	critical
`12`	Internal battery empty exited	Battery charge restored	info
`13`	Internal battery low occurred	Battery charge critically low	warning
`14`	Internal battery low exited	Battery charge above low threshold	info
`15`	External power lost occurred	AC power disconnected	critical
`16`	External power lost exited	AC power restored	info
`17`	External power low occurred	AC voltage below minimum	warning
`18`	External power low exited	AC voltage restored to normal	info
`19`	XDCR fault occurred	Transducer signal loss or fault detected	error
`20`	XDCR fault exited	Transducer fault resolved	info
`21`	O2 pressure low occurred	Oxygen supply pressure below minimum	critical
`22`	O2 pressure low exited	Oxygen supply pressure restored	info
`23`	O2 pressure high occurred	Oxygen supply pressure exceeds maximum	warning
`24`	O2 pressure high exited	Oxygen supply pressure normalized	info
`25`	Defaults set	System reset to factory defaults	warning
`26`	No calibration data found	System startup with missing calibration	error
`27`	Fan fault occurred	Cooling fan malfunction detected	error
`28`	Fan fault exited	Fan fault resolved	info
`31`	Spurious interrupt occurred ms	Microcontroller received unexpected interrupt	error
`32`	Spurious interrupt occurred ls	Microcontroller received unexpected interrupt	error
`33`	ADC mismatch	A/D converter channel mismatch detected	error
`34`	ADC mismatch occurred	A/D converter mismatch first detected	error
`35`	ADC mismatch cleared	A/D converter mismatch resolved	info
`36`	Stepper motor lost sync occurred	Stepper motor lost position synchronization	error
`37`	Stepper motor lost sync exited	Stepper motor sync recovered	info
`38`	Stepper motor home failure occurred	Motor unable to reach home position	error
`39`	Stepper motor home failure exited	Motor home sequence recovered	info
`40`	EEPROM degraded	EEPROM read/write errors detected	error
`41`	Memory CRC check failed	CRC mismatch on stored data	critical
`42`	High pressure occurred	Peak airway pressure exceeds alarm threshold	critical
`43`	High pressure exited	Peak airway pressure returned to normal	info
`44`	Turbine immediate stop occurred	Emergency stop activated on turbine	critical
`45`	Turbine set to zero flow occurred	Turbine flow reduced to zero	warning
`46`	Turbine emergency stop occurred	Turbine emergency stop activated	critical
`47`	Low minute volume occurred	Delivered minute volume below threshold	error
`48`	Low minute volume exited	Minute volume returned to acceptable range	info
`49`	Low peak pressure occurred	Peak inspiratory pressure below threshold	warning
`50`	Low peak pressure exited	Peak pressure returned to normal range	info
`51`	Event log cleared	Event history erased from memory	info
`52`	Control settings cleared	Operating settings reset	warning
`53`	Date set	System date configured	info
`54`	Time set	System time configured	info
`56`	Stack overflow detected	Microcontroller stack memory exceeded	critical
`57`	POST failure	Power-on self-test failed	critical
`58`	Code runaway detected	Software execution exceeded time limit	critical
`59`	Watchdog test run	Watchdog timer test executed	info
`60`	Calibration records cleared	Calibration data erased	error
`61`	Differential pressure transducer narrow channel fault	FDn transducer sensor failure	error
`62`	Differential pressure transducer wide channel fault	FDw transducer sensor failure	error
`63`	Differential pressure transducer bi-directional channel fault	FDb transducer sensor failure	error
`64`	Airway pressure transducer fault	Main airway pressure transducer signal error	error
`65`	AD mismatch primary channel fault value	A/D converter primary channel mismatch	error
`66`	Turbine Hold Stop occurred	Turbine hold stop activated	warning
`67`	Shutdown for other than pressing On/Standby button	Unexpected shutdown detected	error
`68`	EEPROM write error during shutdown	Data write failed to EEPROM at shutdown	critical
`68`	A problem is detected writing data to EEPROM during shutdown	Memory write failure at system shutdown	error
`69`	Problem detected with audible alarm circuitry	Primary or redundant alarm circuit malfunction	warning
`70`	Recovery from audible alarm circuitry problem	Alarm circuit fault resolved	info
`71`	Alarm sounder error	Speaker or sounder malfunction	warning
`72`	Recovery from alarm sounder error	Alarm sounder fault resolved	info
`73`	Reserved for future use	Not currently assigned	unknown
`74`	Reserved for future use	Not currently assigned	unknown
`75`	Reserved for future use	Not currently assigned	unknown
`76`	Reserved for future use	Not currently assigned	unknown
`77`	Reserved for future use	Not currently assigned	unknown
`78`	Reserved for future use	Not currently assigned	unknown
`79`	Reserved for future use	Not currently assigned	unknown
`80`	Reserved for future use	Not currently assigned	unknown
`81`	Reserved for future use	Not currently assigned	unknown
`82`	Reserved for future use	Not currently assigned	unknown
`83`	Reserved for future use	Not currently assigned	unknown
`84`	Reserved for future use	Not currently assigned	unknown
`85`	Reserved for future use	Not currently assigned	unknown
`86`	Reserved for future use	Not currently assigned	unknown
`87`	Reserved for future use	Not currently assigned	unknown
`88`	Reclaims all incorrectly recognized bad EEPROM records	Software 5.01 recovery routine executed	warning
`CAL FAIL`	Calibration procedure failed or aborted	Error encountered during any calibration step (Valve Differential, O2 inlet, or Motor Drive)	error
`DEFAULTS`	Control settings restored to default values	Invalid or out-of-range control settings detected on power up	warning
`DISC/SENSE`	Disconnect or sense circuit failure alarm	Pressure sensing circuit fault or circuit disconnection detected	error
`HIGH PRES`	High pressure condition detected	Airway pressure exceeds high pressure limit setting during ventilation	warning
`HW FAULT`	Hardware fault detected; multiple potential causes	Internal hardware failure or circuit error detected during power-up self-test or operation	critical
`HW FAULT (EEPROM)`	Hardware fault related to EEPROM memory	EEPROM error detected during operation	error
`HW FAULT (INTRRPT1/INTRRPT2)`	Hardware fault related to interrupt errors	Interrupt errors detected during operation	error
`LMV LPPS OFF`	Low Minute Volume alarm is turned off and the LPP ALARM has been set to VC/PC ONLY	LMV LPPS OFF message displayed on ventilator screen	info
`LMV OFF`	Low Minute Volume alarm is turned off	LMV OFF message displayed on ventilator screen	info
`LOW O2 PRES`	Low oxygen pressure condition	Oxygen inlet pressure falls below acceptable level during oxygen delivery	warning
`LPPS OFF`	LPP ALARM has been set to VC/PC ONLY mode	LPPS OFF message displayed on ventilator screen	info
`NO CAL DATA`	Missing or failed calibration data	Calibration data not found or invalid during operation	warning
`RESET`	System reset alarm; ESD or internal reset event	Electrostatic discharge or internal watchdog timer reset during normal operation	warning
`RESET (CRC/POST/RUNAWAY/STACK)`	Reset alarm with various error types (CRC, POST, RUNAWAY, STACK)	Occurs at conclusion of POST after tests that cause ventilator to be inoperative; can also recur repeatedly	warning
`XDCR FAULT`	Transducer circuit fault alarm	Pressure transducer or analog measurement circuit failure detected	error

Likely causes and actions for each code are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.