Q. Why does the control panel display "OH"?
Overheat protection may occur if the pump is set to operate for extended periods.
In extremely hot weather, check for proper cabinet ventilation.
When the hot tub is in a filter cycle, make sure P1 low-speed is on.
Check slice valves. Make sure that they are open.
Check for blockage in the filter cartridge, skimmer basket and pump intake fittings.
Check the alignment of the heater element in the heater housing to make sure it is straight and not contacting the sides.
Make sure the temperature sensor is installed properly.