Lennox 18K43 Limit Switch, Auto Reset, Cut-In Temp 270, Cut-out Temp 300

A Lennox 18K43 Limit Switch interrupts the circuit at unsafe temperatures and restores function once conditions return to range.

• Opting for real OEM switches and buttons reduces unexpected failures by responding accurately under heat so your equipment stays up and running
• Fits Popular Models: GHR26Q2/3-50-01, GHR26Q3-75-01, GHR26Q3-75-02
• Product Type: Limit Switch
• Switch Action: Auto Reset
• Cut in Temperature: 270
• Cut Out Temperature: 300

Common Questions and Answers

What purpose does the Lennox 18K43 Limit Switch fulfill in the system?

The limit switch monitors operating temperature and interrupts or restores the circuit at its rated thresholds to protect the heating and cooling unit from excessive heat. Its auto-reset action and specific cut-in and cut-out temperatures provide dependable response without manual intervention, which matters for maintaining safe, consistent operation in the HVAC system.

What changes in performance might suggest that the Lennox 18K43 Limit Switch should be replaced?

The limit switch might need replacement if the system cycles irregularly, shuts down on temperature more often than expected or could fail to restore normal operation after overheating conditions pass. Physical signs can include visible wear, discoloration or damaged terminals and environmental signs may include exposure to excessive heat buildup, dust or moisture around the heating and cooling equipment.