Understanding the "OH" (Overheat) Error Code on Your Sundance® 880 Series Hot Tub

The Sundance® Spas 880 Series represents premium durability, featuring rigid iTouch™ digital controls, heavy-duty jet pumps, and MicroClean® Plus filtration. Built to withstand Canadian winters, these spas feature integrated safety systems designed to shut down components if unsafe conditions arise.

One critical safety alert on the 880 Series topside display is the OH (Overheat) error code.

An OH code indicates that the temperature inside the heater barrel or main vessel has exceeded safe operating thresholds. Here is why an OH error happens, what immediate safety steps you should take, and how our local technicians resolve it.

What Triggers an "OH" Error Code?

The system monitors water temperatures using two distinct sensors: a temperature sensor inside the tub shell and a high-limit sensor attached directly to the stainless steel heater housing.

When the high-limit sensor reads temperatures above 112°F (44°C) to 118°F (48°C), an OH condition triggers. The spa board shuts down the heater element and engages the jet pumps to circulate water and cool the system.

Primary Causes of Overheating:

1. Low Water Flow: Restricted flow keeps heat trapped inside the heater tube rather than distributing it into the spa shell.
2. Stuck Pump Relays: If a relay on the main circuit board fuses shut, the low-speed circulation pump or jet pump may run continuously, generating friction heat that elevates water temperatures.
3. Out-of-Calibrated Sensors: Temperature or high-limit thermistor sensors can drift in resistance over time, reporting inaccurate high temperatures to the board.
4. Thermal Drift from Extreme Sun/Covering: During warmer periods, prolonged filtration cycles under a heavy thermal cover can trap residual motor heat.

Immediate Steps to Take When "OH" Appears

1. DO NOT ENTER THE HOT TUB: Water at or above 108°F (42°C) can cause overheating and health risks.
2. Remove the Spa Cover: Carefully lift the thermal cover to allow excess heat to dissipate into the ambient air.
3. Do Not Power Down Immediately in Freezing Weather: If the ambient temperature outside in Durham Region or Muskoka is well below freezing, verify if the circulation pump is running. If pumps are moving water, let the system cool down naturally until the code clears.
4. Check Filter Cleanliness: Remove the filter cartridge from your 880 Series spa and check for chemical scale or debris buildup restricting flow through the circulation line.

Professional Repairs for 880 Series Spas

If the water cools down below 102°F (39°C) but the OH code refuses to clear after resetting the GFCI breaker, the high-limit switch or sensor harness likely needs technical replacement.

Leaving a hot tub off during an Ontario winter exposes your plumbing lines to severe freeze risks if the temperature drops rapidly.

If your spa continues to trip or flash overheat codes, visit our main Hot Tub Service & Repair Page to book a technical inspection. For urgent situations where the spa has shut down completely in cold weather, visit our Emergency Hot Tub Repair Page or call 905-862-4040 for direct service dispatch.

To view current features across the lineup, browse our full Sundance® Spas Collection.