TROUBLESHOOTING AN FL2 ERROR CODE
An FL2 error code and FL1 error code are often confused for one another. While an FL1 error code means the spa isn’t sensing enough water flow to close the flow switch, the FL2 error code means exactly the opposite. So when you are troubleshooting an FL2 error code, we want to determine why the spa thinks the flow switch, or the pressure switch, is providing a closed circuit instead of an open circuit.
Generally speaking, an FL2 error code is caused by one of two components, and for three different reasons.
The first reason would be that the flow switch/pressure switch has failed and is delivering a closed circuit at all times. When functioning properly, this sensor should be delivering a closed circuit only when there is adequate water flow. If the sensor is functioning normally, it should measure OL or infinite when no water flow is detected. It should read zero resistance when there is good water flow.
The second reason you may receive an FL2 error is when you are actually receiving water flow and you should not be. In this case, this would likely mean a relay on the circuit board is stuck an a closed position not allowing the pump in question to shut off. This would mean the circuit board needs replaced.
The final reason you may get an FL2 code is because the circuit board may be misinterpreting the information it is receiving from the flow switch or pressure switch. While this is very rare, it would mean a circuit board replacement is necessary.
That said, this is an easy error code to troubleshoot. Does that pump turn on and off like it should? Good, then test the sensor. If the sensor doesn't test like it should, then replace it. If it does test like it should, then replace the board. Now if the pump won't turn on and off like it should, then you likely have a bad board.
- Aqua Paradise