I have a salt water arctic spa model.
When we bought it used we were informed that the second stage of pump 1 had failed - 2 speed pump.
Suddenly FLO turned up which also meant the tub went cool as the heater won't come on without water flowing.
Pump 2 and bubbler work fine.
I replaced pump 1 with a new unit but I still have FLO error and the newly replaced pump 1 won't run.
Before I replaced the motor I checked power running to pump 1 at the control board.
Red at 115v.
Black at 115v when control switched on and I hear the relay click ..... If pump disconnected at side of control panel.
When pump plug connected to control panel this dropped to 40V for both black and red.
Hence why I suspected pump 1 to have failed.
I did notice (but ignored) that white (neutral) was at 110v when tracing through the control panel. This seems very odd. White is definitely neutral when coming into the hot tub.
Any ideas?
