I have a balboa electrical circuit board hot tub. I was getting a half of volt in the water. and did not have a GFI - bad Idea I know. I know have a GFI. The pumps and all were working great. I took the heater apart and replaced the element and put everything back together(It would not get above 95 degrees). After I got it all put back together. It was tripping the GFI. I narrowed it down to the #1 pump. I disconected it and put the number 2 pump in its place. I am getting no read out, no pumping. The circuit board at the #1 plug is reading 220 on the white but nothing on the Black.

I do not know were to go on this. Help please

How are you measuring the voltage? If you're getting 220v on white, then your other probe is on a hot leg. Check the voltage directly at the pump plug. Not sure which is low speed in your case, but white-to-red or white-to-black should give 220v.

But if the display isn't coming on at all you've got different issues. If you have a pressure switch, it's possible it needs to be calibrated. With the spa off, check the continuity across the terminals. If it is closed, you will need to adjust it to a higher psi level (turn the adjustment on the psi switch clockwise).

Also, since your GFI was changed out, check the incoming voltage to be sure:

Line 1 - Neutral = 120
Line 2 - Neutral = 120
Line 1 - Line 2 = 240
Neutral - Ground = 0