I have a 2001 Landmark spa. I just changed the water and I am having the “red flashing” power light problem. I can run all jets for several minutes before the red flashing light comes on. The circulator pump (Silent Flo 5000) is not pumping water and it gets hot after a few minutes of power on. I suspect I have an airlock in the circulator system. Is there a way to fix the problem without having to drain the tub? Any help you can give me it will greatly appreciated.
Regards
Chris

Take the clamp off the pressure side of the pump tubing, then pull the hose off for a second or two before sliding the pipe back onto the pump. Water will gush out, it's messy but effective. Put the clamp back on.

Also, if you want to try something a little less messy, try removing the filter that is isolated to the circ pump, and push a garden hose into that fitting.

If you still have the original circ pump, it may have just bitten the dust. If so, the new ones are pretty cool.

Good luck!