Respironics ESPRIT User manual

REF 580-1000-02 G
ESPRIT®Ventilator
Service Manual

II Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
This work is protected under Title 17 of the United States copyright code and is the sole property of Respironics.
No par of this document may be copied or otherwise reproduced, or stored in any electronic information retrieval
system, except as specifically permitted under United States copyright law, without the prior written consent of
Respironics.
Copyright © 2004-2007. Respironics, Inc.
All rights reserved.
For Technical support, contact:
Respironics, Inc. Customer Service
Within the U.S.A. 1-800-345-6443
Outside the U.S.A. 724-387-4000
Facsimile 724-387-5012
[e-mail]
United States of America
Respironics California, Inc.
2271 Cosmos Court
Carlsbad, CA 92011
USA
1-800-345-6443
or 724-387-4000
Authorized Representative
Respironics Deutschland, Inc.
Gewerbestrasse 17
D-82211 Herrsching Deutschland
[phone]

REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 1
Table of Contents
1 Introduction and Intended Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Recommended Tools and Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
2 Warnings and Cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
General Warnings and Cautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
3 Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Pneumatic System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Delivery System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Ventilator System Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Main PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
CPU PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
Analog PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Digital PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
VGA Controller PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Blower Controller PCB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Motor Controller PCBs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
Sensor PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
Man-Machine Interface (MMI) PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Backlight Inverter PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Real-Time Clock Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Backup Battery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
External Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
DC/DC Converter PCB (use with original 10.4-in. displays only). . . . . . . . . . . . 3-16
Optical Rotary Encoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
Graphic User Interface (GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
Remote Alarm (Nurse Call) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
4 Periodic Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
5 Repair. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Entering Diagnostic Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
User Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Changing the Date and Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Setting the Time Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Compliance Enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Backup Battery/Confirmation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

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Table of Contents
Short Self Test (SST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Extended Self Test (EST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Software Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Diagnostic Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Hardware Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
Flow Control Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
Voltage Control Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
On/Off Hardware. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Solenoid Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Status Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Pneumatic Component Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
Oxygen Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
Oxygen Flow Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-15
Oxygen Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-17
Air Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Air Flow Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19
Inhalation and Exhalation Solenoids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
Safety Valve and Safety Solenoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
Pressure Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-21
Crossover Solenoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22
Exhalation Flow Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
Check Valve 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
Check Valve 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
Check Valve 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
Filter Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Blower. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Inhalation/ Exhalation Pressure Transducers and Exhalation Valve . . . . . . . . . . 5-27
Oxygen Pressure Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
External Oxygen Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
Sensor PCB Voltage Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
Bacteria Filter
Back Pressure Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-30
High Internal Oxygen Alarm Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
6 Diagnostic Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Diagnostic Code 1012 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Diagnostic Code 5000 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-27
7 Ventilator Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Downloading Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Programming the Ventilator Serial Number. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Enabling Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Setting Up the Serial Interface for DRPT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6

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Generating a Diagnostic Report (DRPT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Analog Output Port (Chart Recorder) Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
8 Performance Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Required Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Preliminary Cleaning, Inspection and Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Preliminary Pneumatic Calibration Analyzer Setup . . . . . . . . . . . . . . . . . . . . . . . 8-6
Certifier FA Plus Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Measurement Selection Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Averaging Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Trigger Options Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Configuration Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Saving Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Performance Verification Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-13
Electrical Safety (Test 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-13
Extended Self Test (EST) (Test 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-14
Air Flow Accuracy (Test 3). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-16
Oxygen Flow Accuracy (Test 4). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-18
Pressure Accuracy (Test 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-20
PEEP System (Test 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-21
Breath Rate (Test 7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-24
Alarm/Analog Output Signals, Alarm Volume, and Remote Alarm (Test 8). . . . . 8-25
Gas Volume Accuracy (Test 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-28
Oxygen Accuracy (Test 10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-31
Heated Exhalation Bacteria Filter, Power Fail Alarm, and
Display Intensity (Test 11). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-34
Neonatal Option Testing (Test 12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-36
Backup Battery and External Battery (Test 13) . . . . . . . . . . . . . . . . . . . . . . . 8-38
Returning Ventilator to Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-40
Performance Verification Troubleshooting/Repair . . . . . . . . . . . . . . . . . . . . . . . 8-41
Test 1: Electrical Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-42
Test 2: Extended Self Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-42
Test 3: Air Flow Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-43
Test 4: Oxygen Flow Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-43
Test 5: Pressure Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44
Test 6: PEEP System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44
Test 7: Breath Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44
Test 8: Alarm Output Signal, Volume, and Remote Alarm . . . . . . . . . . . . . . . . 8-45
Test 9: Gas Volume Accuracy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-45
Test 10: Oxygen Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-45
Test 11: Heated Exhalation Bacteria Filter, Power Failure Alarm,
and Display Intensity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-46
Test 12: Neonatal Option Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-46

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Test 13: Backup Battery and External Battery Test . . . . . . . . . . . . . . . . . . . . 8-47
Neonatal Option Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-49
Electrical Safety/Extended Self Test (EST) Data Form . . . . . . . . . . . . . . . . . . . . 8-51
Performance Verification Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-52
9 Component Removal/Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Top Enclosure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
Sensor PCB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-5
Power Supply Fan/Shroud. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
Backlight Inverter PCB (9.5-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Backlight Inverter PCB (Original 10.4-in. GUI only) . . . . . . . . . . . . . . . . . . . . . . 9-8
DC/DC Converter PCB (Original 10.4-in. GUI only) . . . . . . . . . . . . . . . . . . . . . . . 9-9
Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
Power Supply Fuses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-13
MMI PCB (9.5-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-15
MMI PCB (10.4-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-18
GUI Assembly (9.5-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19
GUI Assembly (Original 10.4-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-21
GUI Assembly (2nd Generation 10.4-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . 9-23
Intensity and Volume Potentiometers (9.5-in. GUI) . . . . . . . . . . . . . . . . . . . . . . 9-25
Intensity and Volume Potentiometers (10.4-in. GUI’s). . . . . . . . . . . . . . . . . . . . 9-26
Rotary Encoder (9.5-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-27
Rotary Encoder (10.4-in. GUI’s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-28
GUI Front Panel Overlay (10.4-in. GUI’s). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-29
VGA Display Assembly (9.5-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-30
Touch Screen/LED Indicator Assembly and Front Panel Overlay (9.5-in. GUI) . . . 9-31
Backlight Inverter PCB, VGA Display, and Touch Frame (Original 10.4-in. GUI). . 9-32
Transition PCBA, LCD, IR Touch Frame, and Backlight Inverter PCB
(2nd Generation 10.4-in. GUI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-33
GUI Cleaning and Dust Gasket Installation (2nd Generation 10.4-in. GUI) . . . . . 9-35
Increased Minimum Alarm Volume Harness . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-38
Backup Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-38
AC Distribution Panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-39
AC Cord Bracket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-41
Humidifier Receptacle Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-42
Printed Circuit Boards (Daughter PCBs) (Except Main PCB). . . . . . . . . . . . . . . . 9-44
CPU PCB with 4.10 or Greater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-46
Main PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-47
Remote Alarm Jack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-49
Power Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-50
FIO2Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-50
Exhalation Flow Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-51

Table of Contents
REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 5
Exhalation Valve Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-53
Primary Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-56
Filter Heater Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-56
Oxygen Flow Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-57
Inspiratory Manifold Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-59
Installing the Cable Extension Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-62
Three-Station Solenoid Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-64
Air Flow Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-65
Air Valve Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-66
Oxygen Valve Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-67
Oxygen Regulator Assembly (with Oxygen Pressure Switch) . . . . . . . . . . . . . . . . 9-69
Elapsed Time Meter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-71
Oxygen Water Trap Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-72
Blower Motor Controller PCB (Original) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-73
Blower Motor Controller PCB (Updated) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-74
Blower Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-74
Blower Muffler Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-77
Cooling Fan/Cooling Coil Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-79
GUI Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-81
Replacing the GUI (9.5-in. to original 10.4-in.) . . . . . . . . . . . . . . . . . . . . . . . . 9-84
Installing the CPU and DC/DC Converter PCBs. . . . . . . . . . . . . . . . . . . . . . . . 9-87
Downloading Ventilator Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-87
Calibrating the Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-88
Enabling Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-88
Final Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-88
Replacing the GUI (9.5-in. to 2nd Generation 10.4-in.) . . . . . . . . . . . . . . . . . . 9-88
Installing the CPU PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-90
Downloading Ventilator Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-90
Calibrating the Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-90
Enabling Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-91
Final Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-91
Replacing the GUI (Original 10.4-in. to 2nd Generation 10.4-in) . . . . . . . . . . . . 9-91
Installing the CPU PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-95
Downloading Ventilator Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-96
Calibrating the Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-96
Enabling Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-96
Final Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-96
10 Where to Go for Help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1
11 Esprit Ventilator Replacement Parts List . . . . . . . . . . . . . . . . . . . . . . . 11-1
Esprit Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
GUI Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3

6Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Table of Contents
Oxygen Pneumatics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-5
Air Pneumatics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-7
Exhalation Pneumatics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-9
Inspiratory Pneumatics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-10
Back Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-11
LX-200 Cart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-12
Service Part Inventory List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-13
Complete Repair Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-16
A Pneumatic Schematics for EST. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Block Patient Wye (Test 1, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Block Patient Wye (Test 1, Step 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Block Patient Wye (Test 1, Step 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
Block Patient Wye (Test 1, Step 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-4
Safety Valve (Test 2, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5
Safety Valve (Test 2, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-6
Blower (Test 3, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7
Blower (Test 3, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-8
Oxygen Supply (Test 4, Step 1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-9
Oxygen Supply (Test 4, Step 2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-10
Crossover Circuit (Test 5, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-11
Crossover Circuit (Test 5, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12
Crossover Circuit (Test 5, Step 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-13
Oxygen Delivery (Test 6, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-14
Oxygen Sensor (Test 7, Step 1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-15
Air Delivery (Test 8, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-16
Pressure Relief Valve (Test 9, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-17
Exhalation Valve (Test 10, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-18
Exhalation Valve (Test 10, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-19
Patient Circuit (Test 11, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-20
Patient Circuit (Test 11, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-21
Heated Filter (Test 12, Step 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-22
Heated Filter (Test 12, Step 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-23
B Field Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
C Respi-Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I-1

REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 1-1
Chapter 1. Introduction and Intended Use
The Esprit Ventilator is a microprocessor-controlled, electrically powered
mechanical ventilator. It is intended for use by qualified medical personnel to
provide continuous or intermittent ventilatory support for adult and pediatric
patients as prescribed by a physician. The Esprit Ventilator is intended for use
in either invasive or non-invasive applications.
The Esprit Ventilator meets or exceeds all applicable safety requirements,
consensus guidelines, US regulatory statutes, and international regulatory
standards for life support/mechanical ventilation devices.
Read this manual thoroughly prior to performing service or maintenance on the
Esprit Ventilator. This manual contains advanced troubleshooting, calibration,
and maintenance instructions for the Esprit Ventilator. All maintenance and
repair work should be performed by qualified biomedical technicians who have
received appropriate training and authorization to provide maintenance, repair,
and service for the Esprit Ventilator.
Review the Esprit Ventilator Operator’s Manual and become familiar with Esprit
Ventilator operation before running tests, checking operational readiness or
initiating patient use. The operator’s manual includes important information
about ventilator safety and operation.
Schematic diagrams of the Esprit Ventilator are available upon request.
For additional information about accessories or related equipment, such as
humidifiers and remote alarm systems, refer to the appropriate instruction
manual prior to operating with the Esprit Ventilator.
WARNING: Patients on life-support equipment should be visually monitored by competent
medical personnel, since life-threatening circumstances may arise that may
not activate alarms. Heed all appropriate alarms and follow the instructions
and warnings in this service manual and the operator’s manual. Always check
life-support equipment for proper operation before use.
NOTE: The Esprit Ventilator Operator’s Manual lists all applicable warnings and
cautions. Review these notices thoroughly before operating the ventilator.

Chapter 1
1-2 Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Introduction and Intended Use
Recommended Tools
and Test Equipment The following table lists the recommended tools, test equipment, and
materials required to service and maintain the Esprit Ventilator (Table 1-1).
Test equipment must meet the requirements in Table 1-2.
Description Manufacturer and Model
Test Equipment
Digital multimeter and frequency counter (DMM)
accurate to three decimal places
Local Supplier
Pneumatic calibration analyzer capable of
measuring low pressure (cmH2O), flow rate
(LPM), and volume (liters)
TSI Certifier Plus (Respironics P/N 1040311)
or equivalent
Electrical safety analyzer Dale LT 544D or equivalent
Oxygen analyzer with accuracy of ± 2% TSI Certifier Plus with oxygen sensor kit or
equivalent
Pressure analyzer with accuracy of measuring
high pressure (PSI)
TSI Certifier Plus or equivalent
10 mL calibrated syringe (Neonatal testing) Hans Rudolph 5220 or equivalent
Adapter, USB to serial Respironics P/N 1022895
Analog output port signal selector Respironics P/N 1010891
Esprit Service kit (*included in the kit) Respironics P/N 1021670
Cable, nurse call test* Respironics P/N 1001375
Test adapter, O2 regulator* Respironics P/N 1001376
Cork, silicone* Respironics P/N 1001735 or equivalent
Adapter, parallel port* Respironics P/N 1004644
Test lung, 1 liter* Respironics P/N 1021671 or equivalent
Cable assy, null modem* Respironics P/N 1022815 or equivalent
Ventilator Accessories
Tubing, silicone, 3/16 in. ID x 6.5 ft., PAP Respironics P/N C06686 or equivalent
Adult patient circuit tubes, 42-in. smooth bore
(2 each)
Respironics P/N 1003643 or equivalent
Reusable patient wye, 22mm OD/15mm ID Respironics P/N 1003070 or equivalent
Coupling, silicone rubber Respironics P/N C06348 or equivalent
Tee, plastic with silicone rubber coupling Respironics P/N C06260 or equivalent
Connector, plastic, 22mm OD Respironics P/N C06335 or equivalent
Adapter, O2sensor Respironics P/N 1001736 or equivalent
Hand Tools and Materials
Pliers Local supplier
Needle nose pliers Local supplier
Metric hex key set (rounded ends), 1.5 to 4 mm Local supplier

Chapter 1
Introduction and Intended Use
REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 1-3
Table 1-1: Recommended Test Equipment, Tools, and Materials
Standard hex key set (rounded ends), 0.050 to
5/32 in.
Local supplier
Pen size flat head screwdriver Local supplier
Pen size Phillips head screwdriver Local supplier
#2 flat head screwdriver Local supplier
#3 flat head screwdriver Local supplier
#2 Phillips head screwdriver Local supplier
Torque driver capable of 5 to 25 in.-lbs. Local supplier
5/16 in. open end wrench Local supplier
1/4 in. open end wrench Local supplier
11/16 in. open end wrench Local supplier
#10 metric open end or box wrench Local supplier
1/2 in. open end wrench Local supplier
1 in. open end wrench Local supplier
7/16 in. open end wrench Local supplier
7/32 in. open end wrench Local supplier
9/32 in. socket wrench with removable 6 in.
extension bar
Local supplier
3/16 in. open end wrench or socket wrench Local supplier
5.5 mm open end wrench Local supplier
7 mm open end wrench Local supplier
8 mm box ratchet Local supplier
#10 metric open end wrench Local supplier
#10 metric socket wrench Local supplier
Angled tweezers Local supplier
Wire cutters Local supplier
Tie wraps, 8 in. length Respironics P/N 500-1000-62 or equivalent
Tie wraps, 3 in. length Respironics P/N 500-1000-66 or equivalent
Tie wrap gun Local supplier
Thread tape Local supplier
Loctite 222 Respironics P/N 200-1000-00
Dupont Krytox GPL226 lubricant Respironics P/N 100-1012-00
Static dissipative field service kit Local supplier
Mild detergent or antiseptic wipes Local supplier
PC or laptop (only needed for downloading
software)
Required: Windows 95 or later, serial port and
CD ROM drive
ESD-safe field service vacuum cleaner 3M model 497-AJM or equivalent
Description Manufacturer and Model

Chapter 1
1-4 Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Introduction and Intended Use
Table 1-2: Test Equipment Specifications
Unit of
Measurement Range Accuracy
Pressure -25 to 150 cmH2O 0 to
100 psi
± 1% of reading or ± 0.20 cmH2O (whichever
is greater). ± 2% of reading @ -1 to 38ºC (30
to 100ºF)
Flow (standard) 0 to 300 SLPM ± 2% of reading ± 0.20 SLPM (whichever is
greater)
Torque 5 to 25 in-lbs. ± 1 in-lbs of reading
Volume (STP) 0 to 10 L STP ± 2% of reading ± 0.20 L STP
Voltage DC: ± 5 to 50 V
AC: 2 to 300 V
± 2% of reading

REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 2-1
Chapter 2. Warnings and Cautions
Throughout this manual the following definitions apply:
General Warnings
and Cautions
WARNING: Do not obstruct the emergency air intake near the oxygen water trap/inlet
filter assembly.
WARNING: Never troubleshoot while a patient is connected to the ventilator, since normal
operation is suspended.
WARNING: If the ventilator has been operating, the exhalation filter heater conductor may
be hot. Use caution when removing the filter.
WARNING: To prevent disease transmission, use protective equipment when handling
contaminated bacterial filters or other patient accessories.
WARNING: To avoid personal injury, always disconnect external AC and DC power
sources and high-pressure oxygen sources from the ventilator before
servicing.
WARNING: Explosion hazard. Do no operate the ventilator in the presence of flammable
anesthetic agents.
CAUTION: Troubleshooting and repair should be performed only by a qualified
service technician. Respironics Esprit Factory Service Training is highly
recommended prior to performing service procedures on the Esprit
Ventilator. Contact Customer Service at 1-800-345-6443 or 724-387-
4000 for more information.
CAUTION: Use only Respironics Esprit repair/service parts. Only Respironics parts
are designed for use in this ventilator. Use of non-Respironics repair parts
may alter ventilator reliability resulting in damage. Use of non-
Respironics repair parts will affect your warranty. Contact Customer
Service at 1-800-345-6443 or 724-387-4000 for more information.
CAUTION: Do not modify oxygen diameter index safety systems (DISS) connector on
rear panel. Use only medical grade oxygen.
WARNING: A condition that could cause injury to a patient or operator if the operating
instructions in this manual are not followed correctly.
CAUTION: A condition that could cause damage to, or shorten the service life of,
the Esprit Ventilator.

Chapter 2
2-2 Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Warnings and Cautions
CAUTION: Always ensure that you are following proper electrostatic discharge (ESD)
grounding procedures before handling static-sensitive devices.
CAUTION: Be careful not to pull or crimp any cables, tubes or wires.

REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 3-1
Chapter 3. Theory of Operation
The Esprit mechanical ventilator is a microprocessor-controlled device that can
deliver air, oxygen, or a mixture of air and oxygen to the patient’s lungs in a
predetermined manner to augment or replace the work normally performed by
the patient’s respiratory system. It uses electromechanical control circuits,
flow and pressure monitors, and software programs to deliver breaths as a flow
or pressure controller.
The Esprit Ventilator includes a graphic user interface (GUI), internal blower,
and inspiratory module that mixes air and oxygen. The ventilator can operate
from a 40 to 90 psig (276 to 620 kPa) medical grade oxygen source for
enriched oxygen operation. It also includes multiple communications
interfaces and an internal power supply that can run from a 100 to 240 V AC
50/60 Hz or 24 V DC power sources.
Schematic diagrams of the Esprit Ventilator are available upon request.
Pneumatic System The Esprit Ventilator pneumatic system consists of these subsystems (see
Figure 3-1):
• Internal blower (air source)
• Oxygen regulator (oxygen source)
• Inspiratory module
• Heated exhalation filter assembly
• Exhalation valve assembly
• Expiratory flow sensor
The internal blower generates the air pressure necessary for breath delivery,
eliminating the need for an external source of medical-grade compressed air.
An internal regulator regulates wall oxygen pressure. The ventilator mixes air
and oxygen in the inspiratory module before delivery to the patient.
Based on operator settings, the central processing unit (CPU) controls the air
valve, oxygen valve, and exhalation valve through stepper motor controller
printed circuit boards (PCBs). As flow is delivered to the patient, the air and
oxygen flow sensors and two pressure sensors provide feedback to the CPU.
The pressure relief and safety valves in the inspiratory module provide for
patient safety in the event of an over-pressure condition or any component or
system failure that could interfere with the patient’s ability to breathe when
connected to the ventilator.

Chapter 3
3-2 Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Theory of Operation
The exhalation filter conditions the exhaled gas, reducing the risk of
contamination or component damage due to bacteria or moisture in expired
gases. The exhalation filter is housed in a heated sleeve, which reduces the
relative moisture condensation in the exhalation filter, exhalation valve, and
expiratory flow sensor. Exhaled gas is then vented to atmosphere.
Figure 3-1: Pneumatic System Block Diagram
Figure 3-2 shows the Esprit ventilator pneumatic system and its components.
Figure 3-2: Pneumatic Schematic
Blower
Oxygen
Regulator
Inspiratory Module
• Gas Mixing
• Pressure Relief Valve
• Safety Valve
To Patient
From Patient
Heated
Exhalation
Filter
Assembly
Exhalation
Valve
Expiratory
Flow
Sensor
Room
Air
Oxygen
Supply
Air
O2

Chapter 3
Theory of Operation
REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 3-3
Delivery System The delivery system includes the components that condition and control the
flow delivered to the patient based upon operator-selected parameters. The
blower draws room air through the blower inlet filter (F1) and the muffler
(silencer) and outputs flow to the air valve assembly (AV). A pressure switch
(PS1) monitors oxygen input pressure. The oxygen water trap/inlet filter
assembly filters wall oxygen, and the oxygen regulator (REG1) regulates oxygen
down to 23 pounds per square inch, psi (1.5 kilopascals, kPa). Regulated
oxygen then enters the oxygen valve assembly (OV) and the crossover solenoid
(SOL1). The air and oxygen valves (AV and OV) are controlled by the
microprocessor, based on continuous feedback from the air and oxygen flow
sensors (FS1, T1 and FS2, T2).
Delivery System Components
Blower Inlet Filter
(F1)
The blower inlet filter removes coarse particulate from ambient air as it
is entrained into the blower assembly. See section 4 for periodic
maintenance information.
Cooling Fan Filter The cooling fan filter removes coarse particulate from ambient air
entrained by the cooling fan. See section 4 for periodic maintenance
information
Muffler (Silencer) The muffler reduces the noise of air flow into the blower by channeling
the air through a baffled system lined with sound absorbing material.
Blower The blower draws room air though the air inlet filter and outputs the air
that is delivered to the patient and provides the pilot pressure that can
actuate the safety valve. The blower contains a DC motor and a series of
stator and impeller assemblies. It can provide at least 200 LPM of flow.
Blower speed is automatically adjusted to account for differences in gas
density due to altitude. The altitude can be adjusted from the hardware
screen in diagnostics mode. The High Pressure alarm limit setting also
affects blower speed.

Chapter 3
3-4 Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Theory of Operation
Cooling Coil The cooling coil is a copper tube connected to the outlet of the blower
that reduces the temperature of the gas from the blower before it
reaches the air valve.
Cooling Coil Fan The 24 V DC cooling coil fan removes the heat dissipated by the cooling
coil and blower.
Air Valve Assembly
(AV)
The air valve assembly contains a stepper motor that meters air flow
from the blower to achieve the target flow under CPU control, based on
operator selected parameters. It can deliver up to 200 LPM of flow.
Air Flow Sensor (FS1) The air flow sensor measures flow from the air valve. The ventilator uses
this measurement to provide closed loop control of the air valve and to
compute the flow and volume delivered to the patient. A thermistor in
the flow sensor measures the temperature of the air and provides the
microprocessor with information to compensate the delivered flow.
Oxygen Inlet
Connector (O2)
The oxygen inlet connector provides a country-specific connection point
for an external oxygen gas supply of 40 to 90 psig (276 to 620 kPa).
Oxygen Water Trap/
Inlet Filter Assembly
(F2)
The oxygen water trap/inlet filter assembly consists of a 5-micron (µ)
filter to remove particulate (both dry and liquid) from the oxygen gas
supply, a bowl with drain for accumulated water, and an oxygen inlet
connector.
Oxygen Supply
Pressure Switch (PS1)
The oxygen supply pressure switch is part of the oxygen regulator. PS1
is a normally open (NO) switch that closes when measured pressure is
greater than 40 psig (276 kPa), and provides a digital signal to the
sensor PCB indicating whether supply pressure is adequate at the
oxygen inlet.
PS1 opens if measured pressure is less than 35 psig (241.3 kPa). If the
oxygen supply pressure switch opens during normal ventilation (at O2>
21%), a Low O2Supply alarm results.
Delivery System Components

Chapter 3
Theory of Operation
REF 580-1000-02 G Esprit® Ventilator Service Manual © Respironics, Inc. 3-5
Oxygen Regulator
(REG 1)
The oxygen regulator reduces the oxygen supply pressure to the proper
inlet pressure for the oxygen valve (22-24 psig, or 152-165 kPa @ 180
LPM) and supplies the regulated pressure to the crossover solenoid,
which pilots the safety valve.
Oxygen Valve (OV) The oxygen valve assembly contains a stepper motor that meters flow
from the oxygen regulator to achieve the target flow under CPU control,
based on operator-selected parameters. It can deliver up to 200 LPM of
flow.
Oxygen Flow Sensor
(FS2)
The oxygen flow sensor measures the flow from the oxygen valve. The
ventilator uses this measurement to provide closed loop control of the
oxygen valve and to compute the flow and volume delivered to the
patient. A thermistor contained in the flow sensor measures the
temperature of the oxygen and provides temperature compensation
information to the microprocessor for delivered flow.
Crossover Solenoid
(SOL1)
The crossover solenoid is a three-way valve that supplies either air or
oxygen pressure to pilot (hold) the safety valve closed during normal
ventilation. In its normal state, SOL1 is normally de-energized to pilot
the safety valve with oxygen. If oxygen pressure is lost, SOL1 is
energized and air (rather than oxygen) controls the safety valve.
Check Valve (CV5) The cross contamination check valve prevents the oxygen supply from
entering the air delivery system pneumatics (blower) in the event of a
crossover solenoid leak.
Inspiratory System The inspiratory system includes a manifold where air and oxygen are
blended and the inspiratory pressure transducer (PT3) is connected
through the inspiratory pressure transducer solenoid (SOL4). The
manifold also houses several components designed to ensure patient
safety, including the safety valve pilot solenoid (SOL2), safety valve
(SV), (CV2), inspiratory non-rebreathing check valve (CV3), pressure
relief valve (PRV), and oxygen sensor (OS).
Safety Valve Pilot
Solenoid (SOL2)
The safety valve pilot solenoid directs the output of the crossover
solenoid to the safety valve or vents the pilot pressure line to
atmosphere.
During normal operation, SOL2 is energized and directs pressure from
the crossover solenoid to close the safety valve. During a high priority
alarm condition such as an occlusion or ventilator failure mode (VENT
INOP), SOL2 is deenergized to open the safety valve and allow the
patient to breathe room air.
Delivery System Components

Chapter 3
3-6 Esprit® Ventilator Service Manual © Respironics, Inc. REF 580-1000-02 G
Theory of Operation
Safety Valve (SV) The safety valve contains a spring-loaded diaphragm that is controlled
by safety valve pilot solenoid (SOL 2). Under normal conditions SV is
closed, allowing delivered flow to reach the patient. In the event of a
safety valve open (SVO) condition, pilot pressure is vented to
atmosphere, which opens SV and allows the patient to breathe room air
through the safety port at the rear of the ventilator.
Air System Check
Valve (CV2)
The air system check valve (CV2) prevents oxygen from entering the air
delivery system in the event of a blower failure.
Inspiratory Non-
rebreathing Check
Valve (CV3)
The inspiratory non-rebreathing check valve prevents the patient from
exhaling through the inspiratory limb during a safety valve open
condition, which prevents the patient from rebreathing exhaled gas.
Pressure Relief Valve
(PRV)
The pressure relief valve provides a backup to the operator adjustable
high-pressure alarm and prevents excessive pressures in the patient
circuit. The PRV is spring-loaded to limit the maximum circuit pressure
to 130 to 140 cmH2O.
Oxygen Sensor (OS) The oxygen sensor is an optional device that can be installed between
the 22-mm inspiratory port and the inspiratory bacteria filter. The
oxygen sensor is a galvanic device that measures the oxygen
concentration of the blended gas as it leaves the inspiratory manifold.
The output signal from the sensor is used for the high and low oxygen
concentration alarms. When the sensor is installed and calibrated, the
ventilator alarms if the measured oxygen concentration is not within 6%
of the %O2setting.
Inspiratory Pressure
Transducer (PT3)
The inspiratory pressure transducer on the sensor PCB monitors system
pressure from the inspiratory side of the patient circuit during
exhalation pressure transducer autozeroing, ensuring uninterrupted
pressure monitoring. It is also used with the exhalation pressure
transducer to detect patient circuit occlusions.
Delivery System Components