Error Code
OH error code — Gecko spa
Always cut power at the breaker before opening the spa pack or touching wiring. Spa equipment runs at 120/240V and can be lethal. If you are unsure, hire a licensed spa technician.
Gecko raises OH when water runs past set point by its safety margin. Long pump cycles in summer and drifting sensors cause more OH codes than genuine heater faults.
What OH means
Water temperature over set point plus safety margin.
Diagnose in order
- Check the real water temperature with an external thermometer — the sensor may be lying
- Check whether a pump is running far longer than its programmed cycle
- Test the temperature sensor in the heater — a common, inexpensive failure
- Test the hi-limit sensor — it's separate from the temp sensor
- If the heater keeps running past set point, suspect a stuck heater relay on the board
Likely failed parts
Frequently asked questions
Related codes & guides
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