A sudden change in water pressure (such as someone flushing a toilet or starting up a load of laundry) can cause your shower to go from warm to scalding hot in seconds. To prevent this, you will need to install a pressure-balancing valve in your shower. Kohler's Rite-Temp Pressure-Balancing Valve features a high-temperature limit stop and an optimal comfort zone, allowing you to set a maximum high and then find and maintain your desired water temperature. The unit also works to prevent water temperature from suddenly dipping during instances when hot water is diverted.
Kohler's Rite-Temp Pressure-Balancing Valve can be found at www.supplyhouse.com