I have a Balboa MVS504DZ controller on my Artesian Hot tub. I get OHH reading. I have a circulation pump just for the heater - does not come on. I checked continuity on all 4 fuses. Ok there. The pump was replaced 2 years ago. Pulled plug off pump at controller and checked for voltage. Get 120V on top and bottom pins. no voltage on other pins. The pump is 230V. Could use some guidance.
