I am replacing an old Nu-Wave MM-1 spa pack with a new Balboa VS500Z (50-54219-Z).
I've identified the high and low speed wires going to the pump. Inside the old controller box, and in the old wiring harness, they are black and red, respectively.) I need to remove the old wiring and install the new wire/plug assembly. but the Balboa manual does not specify which is which on the four pin AMP socket on the circuit board. The manual shows the bottom pin is grd, the second is common, but the 3rd and 4th are not specified. The 4th(top) pin is a D shape hole with the flat on the left. The third is round. The corresponding pin on the "21087" wiring harness plug has the red wire attached. So, which are the high and the low pins? Can I assume the colors are connected to correspond to the old harness?