Ohmeda Ohio Care Plus, Operation, Maintenance, Service Manual And Installation Instructions

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6/Service
6-1 6-1
6/Service
In this section
Service Language Notice ..................................................................................................................................6-2
Repair Policy ..........................................................................................................................................................6-9
Functional Description ....................................................................................................................................6-10
Power Supply ..........................................................................................................................................6-10
Microcontroller .......................................................................................................................................6-11
Humidity Sensor ....................................................................................................................................6-11
Humidity Circuit .....................................................................................................................................6-11
Anolog-to-Digital Converter ..............................................................................................................6-11
Watchdog circuit ....................................................................................................................................6-12
Microswitch Circuit ...............................................................................................................................6-12
Safety Relay Circuit ................................................................................................................................6-12
Audio Prompt Circuit ............................................................................................................................6-13
Solid State Relay Circuit .......................................................................................................................6-13
Heater Current Sense Circuit .............................................................................................................6-13
Add Water Circuit ...................................................................................................................................6-13
Membrane Switch Panel Circuit .......................................................................................................6-14
Display Circuit .........................................................................................................................................6-14
Error Codes ..........................................................................................................................................................6-15
E1.1 Heater Control Circuit Failure ...................................................................................................6-15
E1.2 ROM Checksum Error ..................................................................................................................6-15
E1.3 RAM Test Failure ...........................................................................................................................6-15
E1.4 Watchdog Circuit Failure ............................................................................................................6-16
E2.1 Function Execution Error ...........................................................................................................6-16
E2.2 Anolog-to-Digital Converter Error..........................................................................................6-16
E2.3 Membrane Keypad Failure ........................................................................................................6-16
E2.4 Variable Redundancy Error .......................................................................................................6-16
E2.5 Variable Range Error ....................................................................................................................6-16
E3.1 Watchdog Time Out .....................................................................................................................6-16
E4.1 Humidity Sensor Not Connected............................................................................................6-16
E4.2 Humidity Monitoring Circuit ....................................................................................................6-17
E5.1 Calibration Voltage Error (2.5V) ...............................................................................................6-17
E5.2 Calibration Voltage Error (0.0V) ...............................................................................................6-17
E6.1 Thermal Fuse Opened (Heat Assy Fail) ..................................................................................6-17
Repair Procedures .............................................................................................................................................6-17
Lid disassembly & re-assembly .........................................................................................................6-17
Humidifier controller disassembly/assembly ..............................................................................6-18
Humidifier control/display board removal/installation ...........................................................6-20
Humidity Sensor replacement ..........................................................................................................6-21
Sensor calibration .............................................................................................................................................6-23
Valve Checkout Procedure .............................................................................................................................6-24
Electrical Safety Check .....................................................................................................................................6-24