Heat pumps · Error codes · Gree
FLGree · Versati II (R410A)
FL on a Gree Versati II: Water tank water temperature sensor 2 error
Short answer
On a Gree heat pump, FL means: Water tank water temperature sensor 2 error. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Water tank water temperature sensor 2 error.
Part involved: temperature/pressure sensor.
Likely causes:
- The plug on temperature sensor is not correctly connected to the socket on mainboard.
- The resistance of temperature sensor is not correct.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: yes.
What you can check
- Note the code shown on the controller and the unit model numbers (on the rating plate label) before contacting your installer.
- Check the heat pump's breaker/isolator at the consumer unit is on; do not open any casing.
- Check the controller display is lit; a single power cycle at the isolator may be tried only if your installer or manual allows it.
What the engineer will check
- Follow the Gree troubleshooting flowchart for this code in the service manual.
- Check sensor connector and wiring.
- Measure sensor resistance against the manual's sensor table.
- Replace sensor or PCB as indicated by the troubleshooting flowchart.
Who to ask for: Heat pump engineer.
Certification: Heat pump installer competence; F-gas / flammable-refrigerant (R290/R32) handling competence for any refrigerant-circuit work.
What you might notice
Sources
- Air to Water Heat Pump Service Manual Versati II (T1/R410A/50Hz, GC201308-) ↗ · GC201308 · page p.61 (printed; PDF p.64) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026