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

Well if that thing isn't working properly, then everything is going to be hosed.
What I'd do, with the power off, is disconnect the suction line and get the flow going thru the circ pump backwards to ensure that it's full of water and slide the suction line back on... yes you'll might get wet during this time.

Otherwise, if you still don't have flow, I'd replace the circ pump.

I was struggling with a water leak problem and after fixing it i got my water pump airlocked. I looked at this website to get some advice, but before draining my jacuzzi again and disconnecting pipes I tried a simple solution - a toilet plunger. It worked beautifully. I applied a suction to intake inlets at the bottom of jacuzzi. Two or tree fast pushed and pulls and water started flowing again.