Help no power to my hot tub's heater

My hot tub's breaker would trip everytime I switched it to the on position. Through process of elimination I determined that the heating element was bad. I bought a complete new Balboa heater assembly with element plus sensors and installed it. I turned on the breaker, no trip, and checked the top side control. The control showed the actual water temp and the temp the tub is set at. I turned on the pump and both speeds work perfect. Here's the problem, the heater light doesn't come on at the topside control and there's no power going to the heater. I doublechecked all of my connections and everything is connected correctly. Have I overlooked something or is there a reset that I didn't find? My tub is an old Shoreline single pump with a Balboa 58121 heater and Balboa VS500Z circuit board.

 

Welcome to the forums.

The top side heat indicator comes on when everything is ok.
It sounds like your board may not be seeing the correct flow indication.

I will check further.

 

First off thanks for the help PJmax. It's pumping great so is there a sensor that I need to test, reset or replace?