Daikin F3: discharge pipe temperature outside what the circuit allows

What Does Error F3 Mean?

Daikin's malfunction chart lists F3 against discharge pipe temperature. The thermistor on the compressor discharge line has reported a temperature the control will not run at, and because refrigerant flow is what keeps that line cool, the reading is a statement about the circuit rather than about the pipe. Applies to: Daikin outdoor equipment covered by the SM-TS3 malfunction chart, spanning room air, SkyAir, and VRV outdoor units Taken from the Daikin After Sales Service malfunction chart, where the F division belongs to the outdoor unit and the detail code selects the subsystem. Sensor positions and the thresholds behind them come from the service manual for the specific outdoor model, so a code alone does not give you a temperature to compare against. Owner-safe checks: Stop calling for heating or cooling and leave the system off, since each further cycle runs the compressor toward the same limit. | Walk the visible line set and outdoor unit looking for oil film or localised frost, and photograph anything unusual without touching it. | Record how long the outdoor unit runs before it stops, and how performance had changed over the preceding weeks. Qualified technician: Charge measurement, leak detection, recovery, and discharge thermistor testing are certified refrigerant activities under EPA Section 608 and under F-Gas rules in the United Kingdom and European Union. | Adding refrigerant without finding the loss, or restarting to see whether the code stays away, both put the compressor back into the condition the protection stopped.