Bill, you're going to have to provide a little more detail for any chance of accurate advice. Is it an electric shower, or something that looks more like a large knob set into the wall. What are the circustances of it not turning on? Has there been a failure that's been getting worse over time? As much detail as possible please and I'll see if I can help you. Use the Add an Answer button above to supply this info and we can go from there once you have done this.
Rupert, December 2019
