Hello from Duluth again,
I have a Sundance Telluride ( wish different) with a new circuit board and a new pressure switch. Tub is full and NO air in system. (Best that I can tell)

Powr up and pump comes on for a second or two and shuts off. Pump tries to come on again every 30 seconds or so. When it tries for those 2 or so seconds; bubbles are forced out a couple of jets.

The dealer for Sundance has now closed up here and I don't know where else to turn. Thank ya for any help.

Loren

when the pump is off, does it sound like it's humming (in between the times it trys to run)? Which pump is running, the main jet pump or do you have a smaller, circulation pump?