Error Code
OH error code — Balboa 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.
An OH code on a Balboa system means the board measured water hotter than its safety ceiling and shut the heater down. The sensor is wrong more often than the water is genuinely overheating, so verify with a real thermometer before replacing anything.
What OH means
Overheat — water temperature exceeded the safe limit (typically 110–118°F).
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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