Furnace Plenum Thermostat for Lennox, Rheem, 47-21711-08, SHL523

Gas Limit Furnace Thermostat | SHL523 | L130-20F | Replaces Lennox 47-21711-08

Maintain safe furnace operation with this brand-new SHL523 gas limit thermostat. Rated L130-20F, this high-limit switch opens at 130°F and resets at 110°F, helping prevent overheating in residential and light commercial gas furnaces. Designed to replace Lennox® part number 47-21711-08, it delivers dependable thermal protection and OEM-grade performance for consistent heating system safety.

⚙️ Features & Benefits:

• ✅ Opens at 130°F and resets at 110°F (20°F differential)
• Designed for use in gas furnaces and HVAC systems
• Durable construction with secure mounting tabs
• Brand New – Unused and ready to install
• Compact design for easy replacement and universal fit

Replaces Part Numbers:

47-21711-08

✅ Fits Models:

Compatible with select Lennox gas furnace models. Please refer to your unit’s service manual or model tag to confirm compatibility.

️ Installation Tips:

• Disconnect power and shut off gas supply before servicing
• Locate the existing limit thermostat on the furnace heat exchanger or plenum
• Remove mounting screws and disconnect wire terminals
• Install new thermostat in the same orientation and reconnect wires securely
• ✅ Restore power and gas, then test furnace operation and safety cutoff

⚠️ Installation Disclaimer:

This furnace thermostat is intended for use by licensed HVAC technicians or individuals with proper heating system repair experience. Buyer is responsible for verifying compatibility and ensuring safe installation. Improper handling may result in equipment damage, fire hazard, or personal injury. Seller assumes no liability for misuse or incorrect application.

Reliable protection. OEM-grade safety. Restore your furnace’s performance with this high-limit thermostat replacement.