HELP! I am working on a used Morgan SPA and the heater is not turning on. I got the pump/motor working and the blower mototr is working fine. I noticed a white wire cut below the on the tub thermostat control. The other big fat black one goes to the spa pak itself. I am assuming that the cut white wire goes to the thermostat sensor that tells the thermostat how warm the water is. But where the heck does it go to? The control unit or somewhere on the tub plumbing itself? I have looked and looked and looked. I have also tried to run the heater by using the timer. I lift the pegs when I want the heater on, correct? I have enclosed a few pictures of what I am talking about. Here is the top side control panel Here is the underside of the top side control panel Here is a look at the spa pak itself

Yes the timer op is correct. That wire is supposed to contain the sensor, which you can stick inside one of the thermowells on the heater... (bottom of spa control box right side). You'll have to replace the topside control: http://spapartsnet.com/Control-Panels Either the long Len Gordon brand, or the three button Tec Mark with the Adapter plate.