I have an old Kohler single lever shower/tub faucet that is not supplying hot water (warm only). The sink in the same room and the showers and sinks in the other bathrooms all get hot. I looked for the temperature control band described in other forums but this one is old enough it does not have that device. Once I removed the chrome plate I found it does have a brass set screw under the handle but not sure if it controls temperature or which way to adjust.