Hi,

I just go a used hot tub, everything work fine until we start trying changing the temperature using the control knob for the temperature.
The knob was corroded so i think we might have break a part.
I am not sure of the model of our hot tub but I do have the following information:

Control Unit is a

Manufacturer: Ramco
Description: Spa-Temp Control System
Model: ST-1115A

The control panel to turn on/off the jet, light and control the temperarure is made of 2 push buttons ( light and jets) 2 knob to control the air to the jets and a knob to control the water temperature.
The control box is connect to the temperature knob through a , I think, a switch ( liitle black box attach the wire going to control box), from Unimax model WBH 150-9-W.

What would you recommend to fix it or for replacement part?
Thanks for any help.
I can provide picture if needed.