What it means
Daikin's US service manual calls it discharge pipe temperature control. The compressor stops when the pipe passes a set temperature, and the error clears once the pipe has cooled below a lower limit. The system shuts down if the error keeps repeating, and Daikin gives the reset condition as about 60 minutes of continuous running without any other error.
What to check, in order
- Note the code
Write down the code and the full model name for the engineer.
- Reset once at the breaker
Switch off the air conditioner's own breaker for 20 minutes, then switch on and restart. If the code comes back, leave it off and book an engineer.
When to call an engineer
Daikin's service manual lists refrigerant shortage, a faulty discharge pipe thermistor, a faulty expansion valve or coil, a faulty four-way valve, water in the refrigerant, a faulty stop valve and a faulty outdoor control board. Refrigerant work needs an F-gas certified engineer in the UK or an HVAC technician in the US.
A repair visit will usually check the airflow round the outdoor unit, the fans and the refrigerant circuit.
- Note the model and serial number. They're on a label on the side of the indoor unit, and on the outdoor unit.
- Write down the exact code, and what the appliance was doing when it appeared.
- Check whether it's still under warranty. If it is, the repair may cost you nothing.
Quick answers
What does the Daikin F3 error code mean?
The pipe carrying hot gas out of the compressor has got too hot, so the compressor has stopped to protect itself. Daikin's US service manual calls it discharge pipe temperature control. The compressor stops when the pipe passes a set temperature, and the error clears once the pipe has cooled below a lower limit. The system shuts down if the error keeps repeating, and Daikin gives the reset condition as about 60 minutes of continuous running without any other error.
Can I fix Daikin F3 myself?
Engineer only (engineer visit). Start with: note the code; reset once at the breaker. Daikin's service manual lists refrigerant shortage, a faulty discharge pipe thermistor, a faulty expansion valve or coil, a faulty four-way valve, water in the refrigerant, a faulty stop valve and a faulty outdoor control board. Refrigerant work needs an F-gas certified engineer in the UK or an HVAC technician in the US.
Is Daikin F3 worth repairing?
Get a quote first. Often linked to low refrigerant or a valve fault. Get it diagnosed rather than resetting it again and again.
Checked against
- Daikin Service Manual SiUS042113E, FTXM-V / RXM-V inverter pair wall mounted type (manualslib copy of the Daikin PDF)
- Daikin Service Manual SiUS04-924_A, RXS / FTXS H-series inverter pair wall mounted type (PDF)
- Daikin: Simple Self-Diagnosis by Malfunction Code, SM-TS3, list of error codes (PDF)
Last reviewed October 2026. Manufacturers update their pages, and your manual is the final word. Spotted a mistake? Email contact@appliance-error-codes.com.