Sundance Spa OH Error — Overheat Shutdown Fix

What Does This Error Mean?

OH means the water has overheated past the safety limit (typically 110°F / 43°C) and the system has shut down to prevent injury.
Don't enter the water — at OH temperatures it can cause burns within seconds.
Open the cover to let heat dissipate.
Power off at the breaker for an hour minimum.
Most causes: pump runs longer than needed, sensor reading low, or sun-baked spa.

Affected Models

Sundance Optima
Sundance Cameo
Sundance Maxxus
Sundance Constance
Sundance Capri

Common Causes

Pump running too long due to programming or stuck switch
Temperature sensor reading low (heater overshoots)
Cover trapping heat in summer
Ambient sun-baking pushing temp up
High limit sensor failed (no protection trip)

How to Fix It

Open the cover immediately.

Lift the spa cover.
Don't enter the water — at OH temperatures it can cause burns.
Heat dissipates much faster with the cover off.
Wait for water to drop below 104°F before considering use.
Power off at the breaker.

Switch the spa's breaker off.
This stops any further heating attempts.
Wait at least an hour for water to cool.
For summer events, several hours may be needed if the day is hot.
Check ambient conditions.

Is the spa in direct sun?
Has it been a hot day?
Sundance spas with thick covers are well-insulated, which means heat doesn't escape easily on hot days.
If yes, that's likely your OH cause — shade the spa or run filter cycles in cool hours.
Restart and watch.

Once water has cooled below 100°F, restore power.
Let the controller boot and run a normal filter cycle.
Watch the temperature over the next few hours.
If it rises past set point and OH returns, the regulating sensor is failing — service required.
Schedule service if OH recurs.

Persistent OH despite normal ambient conditions points to a failed temperature sensor or thermostat.
Service repair: 150–300 USD typical.
Sundance-authorized techs have the exact OEM parts for your model.
Don't delay — repeated OH events stress other components.

Frequently Asked Questions

How long does it take to cool from OH?

1-3 hours typical to drop from 112°F (OH trigger) to 102°F (use temp), depending on ambient temperature.
Cool, dry days: faster.
Hot, humid days with cover off: faster than with cover on.
Use a thermometer to verify before entering — don't trust the spa's display while OH is active.

Why does OH happen on the same day every year?

If OH appears on the hottest summer days consistently, it's an ambient + cover insulation issue.
Workarounds: thinner cover, shading the spa, scheduling filter cycles for early morning/late evening.
Some users disable the auto filter cycles in midsummer and run them manually in cool hours.