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

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