Display shows OH or OHH, spa shuts down, pumps may run briefly then stop, water feels excessively hot.

Safety: Do not use the spa when an OH/OHH condition is present. Turn off power at the breaker before working on the spa.

• Remove cover and cool water: Remove the spa cover and allow the water to cool to below 100°F (38°C). You can add some cool water to speed cooling, but do not shock the shell with very cold water.
• Check for flow issues: Inspect and clean the filter, verify water level, and ensure all valves are open. Low flow can cause the heater tube to overheat and trip the high-limit.
• Reset power: After the water has cooled, turn the breaker OFF for 5 minutes, then back ON. See if the OH code clears and normal operation resumes.
• Inspect circulation: Confirm that the circulation pump is running when the spa calls for heat. You should feel water movement at the heater return jet. If there is little or no flow, troubleshoot the circulation pump and flow switch.
• Check sensor placement: In the equipment bay, verify that the temperature and high-limit sensors are fully inserted into their wells on the heater tube and that the wires are intact.

If OH/OHH returns quickly, the heater relay on the Saratoga Spas control board may be stuck closed or the high-limit sensor may be faulty. These components should be tested and replaced by a qualified technician.