Hot Tub Trouble Codes

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Hot tubs provide their owners with error codes that help diagnose any problems occurring in them. While not every problem has a diagnostic code, you can diagnose a few major problems through these codes and make needed corrections.


Standard codes for hot tubs include COL, ICE, Sn1, Sn2, FL1, FL2, OH and ---. COL indicates

The first two deal with temperature; the tub will turn on to maintain a heat level or protect itself against freezing temperatures. The others deal with specific problems regarding sensors, water flow and overheating.


The codes Sn1 and Sn2 indicate problems with the heater or temperature sensors. You most likely need help to correct these problems with your hot tub. Flashing FL1 and FL2 indicates flow switch, filter or air lock problems. Codes OH and --- indicate that the hot tub is overheating the water.

Corrective Actions

For FL1 and FL2 codes, you can perform three actions: verify that the tub's water level is sufficient; clean the filter; or purge the circulation pump of excess air. Turn off the power to reset the tub's systems. For code OH, remove the hot tub cover and set the tub to the economy setting. The --- code will require help from an authorized technician.