In brief
Fault code 01 on Hitachi Utopia / Set Free / Cassette means: Fault code 01 indicates that the indoor unit safety device (float switch) has detected a high water level in the condensate tray. Most common cause: Failed condensate pump, float switch stuck in the raised position, blocked condensate drain, or faulty PCB. First action: Check if the tray is full. If so, the drain is blocked or the pump is not running.. Call a registered engineer if the fault returns after basic checks or involves refrigerant work (F-Gas registered engineer required).
According to the Hitachi Service Manual, the float switch detects a high water level in the condensate tray to prevent overflow.
01 • Hitachi • Utopia / Set Free / Cassette
Fault code 01 Hitachi: Condensate tray safety
Fault code 01 indicates that the indoor unit safety device (float switch) has detected a high water level in the condensate tray.
Source: Hitachi Service Manual - Utopia Series
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What does fault code 01 on Hitachi mean?
Fault code 01 indicates that the indoor unit safety device (float switch) has detected a high water level in the condensate tray.
Failed condensate pump, float switch stuck in the raised position, blocked condensate drain, or faulty PCB.
Symptoms
- Indoor unit stops (overflow safety)
- Code 01 displayed on the central controller
Diagnosis
1. Inspect the condensate tray
- Check if the tray is full. If so, the drain is blocked or the pump is not running.
- Clean the safety float switch.
2. Test the pump
- Check the power supply to the condensate pump.
- Check that the drain hose is not kinked.
How to reset fault code 01 on Hitachi?
Clear the drain, clean the tray/float switch or replace the condensate pump.
When should you call an F-Gas engineer?
Fault code 01 most commonly appears during cooling operation, especially on Utopia / Set Free / Cassette models. Indoor unit stops (overflow safety).
Field context
Fault code 01 most commonly appears during cooling operation, especially on Utopia / Set Free / Cassette models. Indoor unit stops (overflow safety).
Frequently asked questions
Can I use the air conditioning with error 01?
No, it locks out to prevent water leaking from the ceiling.
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