Rheem-Ruud 47-102473-03 Limit Switch

The Rheem-Ruud 47-102473-03 Limit Switch is a critical safety component designed for high-limit thermal protection in residential and commercial furnaces. This SPST normally closed switch is engineered to monitor heat exchanger temperatures and break the electrical circuit if the internal temperature exceeds the 190°F open temperature threshold. Once the system cools to the 170°F close temperature, the auto-reset mechanism restores the circuit, allowing for continued operation without manual intervention. Featuring a 3-inch insertion length, this board-mounted switch provides precise temperature sensing within the airflow, ensuring an accurate response to potential overheating conditions. This part serves as the direct replacement for 47-21711-03 and is frequently utilized across a wide range of Rheem and Ruud gas-fired heating equipment. For contractors performing furnace limit switch replacement, this genuine OEM part ensures exact electrical specs and physical fitment for maintaining system integrity and safeguarding against thermal stress.

Key Benefits

• OEM Compatibility: Serves as the factory-authorized replacement for 47-21711-03, ensuring HVAC part compatibility and simple installation.
• Precise Thermal Control: Fixed 190°F open and 170°F close setpoints prevent furnace overheating and protect the heat exchanger from damage.
• Automatic Reset: Eliminates service calls for nuisance trips by resetting the circuit once temperatures return to a safe 170°F range.
• Optimized Probe Depth: The 3" insertion depth reaches the ideal sensing zone within the furnace cabinet for reliable temperature monitoring.
• Durable Construction: Built for high-limit switch applications, the board-mounted design is resistant to the vibration and thermal cycling common in HVACR environments.

Common Questions

Why is my furnace blower running but there is no heat?
A tripped 47-102473-03 limit switch often causes the blower to run continuously to cool the heat exchanger while the burners are disabled for safety. Check for restricted airflow, such as a dirty filter or blocked return air.

Can I use this switch in place of a manual reset limit?
No, this is an auto-reset limit switch. Always match the reset type and temperature ratings of the original manufacturer specifications to ensure proper system safety logic.

What are the symptoms of a failing limit switch?
Common indicators include furnace short-cycling, the system "locking out" on a limit error code, or the burners failing to ignite despite a call for heat.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.