OEM Lennox Limit Switch — 27H47

The genuine OEM Lennox 27H47 limit switch is a critical safety control that monitors the temperature inside your furnace heat exchanger. When the internal temperature climbs beyond the rated setpoint, this switch interrupts the burner circuit to prevent overheating and protect your Lennox equipment from damage. It also helps regulate blower operation so conditioned air is delivered at the proper temperature.

Common failure symptoms: If the 27H47 fails, you may experience short cycling, a furnace that shuts down before reaching the set temperature, no heat, or the blower running continuously. A limit switch that trips repeatedly often points to restricted airflow or an overheating condition that should be inspected alongside replacement.

Why OEM matters: Lennox limit switches are calibrated to precise trip temperatures matched to your specific furnace model. An OEM 27H47 guarantees the correct setpoint, terminal configuration, and mounting fit — ensuring reliable safety protection that generic aftermarket switches cannot promise. Protect your investment and keep your system operating within factory specifications with a direct-fit genuine Lennox replacement.