Error Code
Sn3 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.
Sn3 flags the heater's temperature sensor as electrically failed. Sensors age in hot chlorinated water, so this is routine maintenance more than a fault — and the part is inexpensive.
What Sn3 means
Heater sensor failed — open or shorted.
Diagnose in order
- Power-cycle once to rule out a glitch
- Check the connector at the board
- Replace the temperature sensor; consider doing the hi-limit at the same time
Likely failed parts
Frequently asked questions
Related codes & guides
Not sure which part failed?
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