Common Mitsubishi Electric AC Fault Codes: What They Mean and How to Fix Them – Canberra
If you own a Mitsubishi Electric air conditioner in Canberra, ACT, and it starts flashing mysterious fault codes, you’re not alone. These codes are built-in diagnostic tools to help identify what’s wrong—but understanding them requires some know-how. In this guide, Air Turners walks you through the most common Mitsubishi Electric AC fault codes, what they mean, and what you can do about them.
🛠️ Important: Some repairs require a licensed air conditioning technician in Canberra. If you’re not qualified, it’s safer and smarter to call a professional.
Mitsubishi Electric AC Systems
Why Your Mitsubishi Electric AC Is Displaying Fault Codes
Mitsubishi Electric air conditioners are built to be reliable, but like all advanced machines, they include error detection to protect the system. When something goes wrong whether it’s temperature imbalance, a sensor failure, or power issues—the unit flashes a fault code.
⚠️ Top Mitsubishi Electric Air Conditioner Fault Codes (and What They Mean)
H2 – Indoor Thermistor Fault
- What it means: The thermistor is not reading the indoor temperature properly.
- Possible cause: Loose connection, a faulty sensor, or internal board fault.
- Action: Check the wiring or replace the thermistor. Requires a technician.
P8 – Outdoor Thermistor Fault
- What it means: The outdoor unit can’t measure temperature correctly.
- Possible cause: Weather damage, worn-out sensor, or wiring issues.
- Action: The sensor needs testing and likely replacement.
E9 – Drain Pump Fault
- What it means: Water isn’t draining from the indoor unit correctly.
- Possible cause: Blocked or broken drain pump.
- Action: Inspect for clogs or pump malfunction. Must be serviced by a licensed technician.
U4 – Communication Fault
- What it means: There’s a communication issue between the indoor and outdoor units.
- Possible cause: Damaged communication cable, incorrect wiring, or PCB failure.
- Action: Check cabling; may require control board diagnostics.
L3 – Outdoor Power Supply Problem
- What it means: The outdoor unit isn’t getting a stable power supply.
- Possible cause: Power surge, fuse problem, or wiring issue.
- Action: Only a licensed electrician or HVAC tech should handle power faults.
F1 – Indoor Fan Motor Fault
- What it means: The indoor fan motor isn’t operating correctly.
- Possible cause: Obstruction, faulty motor, or control issue.
- Action: Replace motor or PCB if needed.
🔧 When to Call a Licensed AC Technician in Canberra
Some Mitsubishi fault codes can be resolved with basic cleaning or a reset, but may involve:
- Electrical diagnostics
- Sensor replacement
- PCB (Printed Circuit Board) troubleshooting
- Safe handling of refrigerants (legally restricted in Australia)
For these, Air Turners in Canberra offers fast, professional, and fully licensed air conditioning repairs. We service both residential and commercial Mitsubishi Electric AC systems.
✅ Preventative Tips to Avoid Mitsubishi Electric Faults
Keeping your system in top shape can reduce the risk of faults. Here’s what you can do:
- Clean your filters monthly
- Book annual professional servicing
- Check your outdoor unit for leaves and debris
- Never block airflow around indoor vents
- Install a surge protector for your AC
📍 Why Choose Air Turners Canberra for Mitsubishi AC Repairs?
- Licensed and experienced HVAC technicians
- Specialising in Mitsubishi Electric air conditioning systems
- Same-day and emergency repair options
- Locally trusted in Canberra, ACT and surrounding suburbs
- Transparent pricing and honest service
📞 Need AC Help? Contact Air Turners Today
If your Mitsubishi Electric air conditioner shows a fault code, don’t wait for it to worsen. Call Air Turners Canberra on 02 6294 4443 Number] or Book Online to schedule a licensed inspection.
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