Optimum Pool Technologies 42002_0025S Gas Shutoff Switch Replacement for Pentair MasterTemp and Max_E_Therm Heaters _ Replaces 42002_0025S

The Gas Shutoff Switch is an important switch in your Max-E-Therm or MasterTemp pool heater, and is used to detect when your heat exchanger outlet temperature has exceeded a safe level (140°F) and the switch immediately opens when that happens. Your MasterTemp heater will indicate when it is time to replace the High Limit Switch when the "AGS" LED is displayed. Compatibility: Pentair MasterTemp (All Models) & Max-E-Therm (Models SR200, SR333, SR400) Heaters. Replaces: 42002-0025S and 42001-0064S.