It’s common to have a circulation pump airlock after re-filling your spa. An airlock should be addressed immediately because it won’t take much time for the motor to overheat and burn out— even a new one.
Without bubbles shooting out from the foot well, there will also be a “flow error” message on the upper control panel and the heater will not turn on.
Air bubbles should be shooting out of the ozone/heater port in the foot well, about 18 inches. If not…
Remove the air bleeder valves near the filters. There should be a constant stream of bubbles from the ozone bleeder valve port. If not…
Turn off power at the GFCI.
Remove the ozone filter from its canister.
Put a garden hose directly over the ozone bleeder port and force water into the opening. With any luck, air bubbles will be forced through the plumbing and come out the foot well of the spa.
Turn on the GFCI. The circulation pump should run, bubbles should shoot out of the foot well, and the upper control display should read normally.
If not… turn off the power again at the GFCI.
When the circulation pump is operating normally, replace the bleeder valves, filters, and filter covers.
Turn on power at the GFCI to see if the error message is gone and the bubbles are flowing again.
Hold the running hose over the ozone port in the foot well and watch for bubbles to come through the port by the filter. You may have to repeat this top and bottom routine up to 3 times to purge all the air from the circulation pump plumbing.