zsqure

Awesome, that answers my question, heat board it is then. Thank You!

Can I hook the heater to a plug, plug it into the wall and see if the heater will work that way?

"If the "heater on" light is on but there is no voltage to the relay where the black and white wires connect then the relay board is bad" That sounds like a solution, but I do have power at the output of the heater board if I check it black to ground or white to ground. If i check it black to white there is no power. AM i HAVING A MENTAL BLOCK CONCERNING THIS?

Ok, I am at the end of my rope. I have a sovereign model hot spring spa. It has the original no fault 6000 heater, the heater board was replaced a couple years ago. It looks like the newest board, and has black colored relays. My spa was working fine until I changed the water. The leds on the main board indicate the heat circuit is on. the heater has a resistance of 9.8 ohms. It has power going to it, the power outputs on the heat board have 120v when I check white to ground and 120v when I check black to ground. If I check black to white there is no voltage. I removed the cover over the reset switch and checked power there, 120v on each side of the switch (black wire to ground). The circulation pump is circulating, i can see ripples on the surface. I have removed the filters in order to reduce resistance in water flow. i dont know why it is not heating.