DIY HVAC Tools

Daikin mini split error code F3

Discharge pipe temperature too high.

  • TypeProtection
  • SystemCompressor / inverter
  • Can I fix it?Homeowner checks, then maybe a tech

What F3 means on a Daikin

The refrigerant leaving the compressor got hotter than the safe limit. The compressor stops.

On this platform, F3 is a protection: the system stopped or throttled itself to prevent damage; many clear on their own once conditions return to normal.

Common causes

  • Low refrigerant charge.
  • A blocked outdoor coil or failed fan.
  • A partly closed service valve.
  • A failing compressor.

How to fix it yourself

Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician.

  1. Look at the outdoor unit: clear leaves, cottonwood fluff, snow or ice from the coil and make sure the fan can spin freely and nothing is stacked against the cabinet.
  2. Confirm the service valves are fully open.
  3. Cool down with power off for 30 minutes and retry.
  4. Anything inside the refrigerant circuit (sensors are fine, but valves, compressors and leaks are not) needs EPA-certified refrigerant handling. That is a technician job.

Switch off power at the breaker before opening either unit. Capacitors in the outdoor unit hold a charge for several minutes after power is cut.

When to call a technician

Recurring F3 with a clean coil needs a charge check.

Which Daikin units show F3

This page applies to Daikin Aurora, 19 Series, Atmosphera, Emura, Quaternity and MXS multi-zone units. Daikin's own documentation lists F3 as "Discharge pipe temperature too high", the same definition used across the Daikin it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.

Where Daikin shows this code

Most Daikin wall units do not show the code on the unit; the operation lamp blinks. To read the code, point the remote at the unit, hold CANCEL (or Timer Cancel) for about 5 seconds until 00 shows, then press CANCEL repeatedly. Each press shows a code; when the unit gives a long continuous beep instead of two short beeps, the code on the remote is the stored fault. Units with a wired controller show the code directly. A and C codes are indoor-unit faults, E, F, H, J, L and P codes are outdoor-unit faults and protections, and U codes are system-level problems such as communication, power supply and refrigerant shortage.

Other Daikin codes

Same part of the system as F3:

E5Compressor motor lock or overloadE6Compressor start failureH6Compressor position detection fault (start-up failure)L4Inverter heat sink (radiation fin) overheatingL5Inverter instantaneous over-current (DC output)L8Electronic thermal overload (compressor over-current)L9Stall prevention (compressor start-up failure)
00No fault stored (normal)A1Indoor unit control board (PCB) failureA3Drain water level abnormal (float switch)A5Freeze-up protection (cooling) or high-pressure control (heating)A6Indoor fan motor fault (locked or abnormal)A9Indoor electronic expansion valve (EEV) faultC4Indoor heat exchanger (liquid pipe) temperature sensor fault (open or short circuit)C5Indoor heat exchanger (gas pipe) temperature sensor fault (open or short circuit)

All Daikin error codes

F3 on other brands

The same characters do not always mean the same thing. Check the brand on your unit.

  • Pioneer F3 Compressor discharge temperature sensor (TP) open or short circuit / Zone C indoor coil outlet sensor (T2B) fault, shown on the outdoor display
  • Blueridge F3 Outdoor ambient temperature sensor fault (open or short circuit) / Compressor discharge temperature sensor (TP) open or short circuit
  • Gree F3 Outdoor ambient temperature sensor fault (open or short circuit)
  • Zone Air F3 Outdoor coil temperature sensor fault protection
  • Carrier F3 Compressor discharge temperature sensor (TP) open or short circuit
  • Heil F3 Compressor discharge temperature sensor (TP) open or short circuit / Outdoor ambient temperature sensor fault (open or short circuit)
  • ACiQ F3 Compressor discharge temperature sensor (TP) open or short circuit / Outdoor coil temperature sensor fault protection
  • Goodman F3 Discharge pipe temperature too high

Questions people ask

Can I reset a Daikin F3 code myself?

Yes. Turn the system off at the breaker for five minutes, then restart it. If F3 comes back, the fault is real and needs the checks above.

Is it safe to keep running a Daikin showing F3?

Not repeatedly. A protection code means the unit stopped itself to prevent damage, and resetting it over and over can turn a cheap repair into a compressor failure. Reset once, check the basics, and stop if it returns.

Do I need a technician for Daikin F3?

Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician. Recurring F3 with a clean coil needs a charge check.

Sources

  • Daikin residential (RA) service manuals (error code tables)
  • Daikin operation manuals (remote controller self-diagnosis)

Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.