Daikin - ⛔ Do Not Use

Daikin - Error Code C5

Q: "What does Daikin Heat Pump error code C5 mean?"

"Error code C5 on a Daikin heat pump indicates: Thermistor malfunction (gas pipe sensor). The unit has detected this condition and has limited or stopped operation to prevent further damage."

Q: "How do I fix Daikin Heat Pump error code C5?"

"Start by powering the unit off for 30 seconds and restarting. If error C5 returns, the underlying cause (thermistor malfunction (gas pipe sensor)) needs to be addressed. Check wiring connections and filters first before replacing components."

Q: "Is Daikin error code C5 serious?"

"It depends on the root cause. Some C5 errors resolve with a reset. Others indicate a failed component that requires professional repair. Don't continue operating with this error — it can lead to further damage."

Daikin Heat Pump error code C5: Thermistor malfunction (gas pipe sensor).

Is it safe?

⛔ No — stop using

Do NOT operate — potential gas or CO hazard. Ventilate the area and call a technician immediately.

Can I fix it?

Technician Required

Repair cost

Pro: $150–$600

⏱ 1–3 hours (pro)

What Does Error Code C5 Mean?

Daikin Heat Pump error code C5: Thermistor malfunction (gas pipe sensor).

Part that typically fails: Gas valve / igniter / heat exchanger

Do NOT operate — potential gas or CO hazard. Ventilate the area and call a technician immediately.

Symptoms You May Notice

⚠️ Inaccurate temperature control
⚠️ System runs constantly
⚠️ Error on control board

What the Technician Will Do

🔧 Professional repair required. Do not attempt DIY — this repair requires specialized tools or certification.

1 Check your owner's manual for model-specific guidance on error code reset procedures
2 Test the temperature sensor with a multimeter — replace if reading is outside spec
3 Inspect sensor wiring harness for damage or loose connections
4 If the error persists after reset and basic checks, contact a qualified technician

⚡ Quick tip: Always try a full power reset first — turn the unit off at the breaker, wait 30 seconds, restore power.

Frequently Asked Questions

What does Daikin Heat Pump error code C5 mean? ▼

Error code C5 on a Daikin heat pump indicates: Thermistor malfunction (gas pipe sensor). The unit has detected this condition and has limited or stopped operation to prevent further damage.

How do I fix Daikin Heat Pump error code C5? ▼

Start by powering the unit off for 30 seconds and restarting. If error C5 returns, the underlying cause (thermistor malfunction (gas pipe sensor)) needs to be addressed. Check wiring connections and filters first before replacing components.

Is Daikin error code C5 serious? ▼

It depends on the root cause. Some C5 errors resolve with a reset. Others indicate a failed component that requires professional repair. Don't continue operating with this error — it can lead to further damage.

More Daikin - Error Codes

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