Lennox 42J04 Auto Limit Switch 135°F-175°F

The Lennox 42J04 is an automatic limit switch, it is a safety device that is used in numerous HVAC systems, it plays the role of a temperature watchdog that supervises the internal temperature of the system. In the event that the temperature goes high, normally between 135 degrees Fahrenheit and 175 degrees Fahrenheit, the limit switch turns off the unit to avoid overheating and subsequent damage. The Lennox 42J04 comes with 24V systems, has the frequency of 50Hz. It also serves as a temperature control device by observing the internal temperature of the system.