6/Service
6-10 6-10
E2.3
Membrane Keypad Failure
As part of the OLSTs, a routine tests if any of the switches on the membrane keypad
are shorted. If this occurs, this error is displayed. Replace the membrane keypad. If the
problem persists, replace the microcontroller.
E2.4 Variable Redundancy Error
As part of the OLSTs, a routine tests the redundantly stored variables. All of the critical
variables and data are stored in three places in RAM. If these three are not equal, this
error is displayed. Replace the microcontroller.
E2.5 Variable Range Error
As part of the OLSTs, a routine tests each variable (actual RH, set RH, etc.) for valid
values. If any variable has an invalid value, this error is displayed. To check the
humidity sensor, attach a voltmeter to the two-pin header, H1, on the board; positive
to pin 1 and negative to pin 2. Turn the unit on in room ambient humidity and check
that the voltmeter reads between 1.0 and 3.5v. If it falls outside this range, replace the
sensor. If it is inside this range, replace the microcontroller.
Note: This code can appear when the sensor and calibration bottle are not stabalized.
Wait 30 minutes for them to fully stabilize.
E3.1 Watchdog Time Out
The output of the watchdog circuit is an interrupt to the microcontroller. If the software
is lost or the microcontroller is malfunctioning, the watchdog will interrupt the
microcontroller. If this happens, this error is displayed.
Replace the microcontroller. If this problem persists, replace the board.
E4.1 Humidity Sensor Not Connected
On power up, a logic level on the humidity sensor connector is queried. If the sensor is
not connected to the board, this error is displayed. Connect the sensor and verify the
jumper is on the connector. If the problem persists, replace the board.
E4.2 Humidity Monitoring Circuit
On power up, the ADC reads a resistor (JP3) on the board. If this value is invalid, this
error is displayed. Replace the board.
E5.1 Calibration Voltage Error (2.5V)
As an on line test, the calibration voltage of 2.5V is measured. If this test fails, the ADC
must be in error, and the error displayed. Replace the microcontroller.
E5.2 Calibration Voltage Error (0.0V)
As an on line test, the calibration voltage of 0.0V is measured. If this test fails, the ADC
must be in error, and the error displayed. Replace the microcontroller.
E6.1 Thermal Fuse Opened (Heater Assembly Failure)
When heat is turned on, the heater current sense circuit shows the status of the
thermostat and thermal fuse. If the thermal fuse opens, this error is displayed.
Replace the heater assembly.
Summary of Contents for Ohio Care Plus
Page 20: ...2 General Information 2 4 2 4 Notes...
Page 24: ...4 Using the Servo controlled Humidifier 4 2 4 1 Notes...
Page 46: ...6 Service 6 18 6 18...
Page 53: ...8 Schematics 8 1 Figure 8 1 Wiring Diagram Servo controlled Humidifier 8 Schematics CI 18 059...
Page 55: ...8 Schematics 8 3 Figure 8 3 Digital section of the Control Display Board Assembly CI 18 061...
Page 56: ...8 Schematics 8 4 Figure 8 4 Analog section of the Control Display Board Assembly CI 18 062...
Page 58: ...8 Schematics 8 6 Figure 8 6 Display section of the Control Display Board Assembly CI 18 064...
Page 67: ......