In brief
Fault code 1C on Toshiba Digital Inverter means the inverter PCB cannot drive the compressor from start-up. Most common cause: unstable supply voltage or a faulty outdoor control board. First action: measure 230 V or 400 V at the outdoor unit input, off-load.
According to the Toshiba Troubleshooting Guide, code 1C is a compressor-control (inverter) fault: unstable supply voltage, faulty control board, or a mechanically stiff compressor.
1C • Toshiba • Digital Inverter
Fault code 1C Toshiba: Compressor control fault
Similar to code 14 but more 'control' oriented, code 1C indicates that the PCB cannot control the compressor correctly from start-up.
Source: Toshiba Troubleshooting Guide
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What does fault code 1C on Toshiba mean?
Similar to code 14 but more 'control' oriented, code 1C indicates that the PCB cannot control the compressor correctly from start-up.
Unstable supply voltage, inverter PCB fault, or mechanically stiff compressor.
Symptoms
- Attempts to start then fails (3 attempts then error)
- No cooling output
Diagnosis
1. Voltage check
- Check stability of 230V/400V at the outdoor unit input.
2. Cross-test
- If possible, connect a test compressor or check PCB outputs with an oscilloscope or inverter tester.
How to reset fault code 1C on Toshiba?
Replace the main outdoor PCB. Also check compressor integrity.
When should you call an F-Gas engineer?
Code 1C most often appears during air conditioning operation, especially on Digital Inverter. Attempts to start then fails (3 attempts then error)
Field context
Code 1C most often appears during air conditioning operation, especially on Digital Inverter. Attempts to start then fails (3 attempts then error)
Frequently asked questions
What does code 1C mean?
Similar to code 14 but more 'control' oriented, code 1C indicates that the PCB cannot control the compressor correctly from start-up.
What is the most common cause of 1C?
Unstable supply voltage, inverter PCB fault, or mechanically stiff compressor.
How to diagnose 1C in the field?
Voltage check: Check stability of 230V/400V at the outdoor unit input.
How to resolve fault 1C?
Replace the main outdoor PCB. Also check compressor integrity.
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