Berko 4520-0015-000 Limit Switch

The Berko 4520-0015-000 Limit Switch is a critical safety component designed for precise thermal regulation in forced-air heating systems and HVAC equipment. This 96-165F Auto Limit Switch monitors internal plenum temperatures, automatically breaking the electrical circuit if the temperature exceeds the 165°F threshold to prevent heat exchanger damage or hazardous conditions. Once the system cools to the 96°F reset point, the automatic reset functionality restores the circuit without manual intervention, ensuring continuous operational uptime for the Marley Engineered Products heater units it supports.

For field technicians, this OEM replacement part is essential for maintaining the factory-specified safety sequence of Berko and QMark heaters. Its bimetal disc sensor provides high-accuracy temperature sensing and rapid response times, making it a reliable thermal cutoff protector in demanding commercial and residential environments. Ensure electrical power is disconnected before integrating this HVAC safety switch into your existing wiring harness.

• Factory-Calibrated Precision: Fixed 96°F to 165°F range eliminates the need for field adjustments and ensures reliable cycling.
• Automatic Reset Logic: Reduces service calls by restoring system power once temperatures return to safe operating levels.
• Broad Compatibility: Engineered specifically for Marley, Berko, and QMark heating units requiring a 4520-0015-000 specification.
• Durable Construction: Built to withstand high-cycle thermal stress in heavy-duty HVAC applications.

• What causes this limit switch to trip repeatedly? Frequent tripping usually indicates restricted airflow, such as a clogged filter, failing blower motor, or undersized ductwork causing the unit to overheat.
• Can I use a manual reset switch in place of this auto-reset model? No. It is vital to use the specific automatic reset configuration designated by the manufacturer to maintain the correct safety sequence and system logic.
• How do I verify if the 4520-0015-000 is failing? Use a multimeter to check for continuity; at room temperature, this switch should remain closed. If it stays open when cool, the internal bimetal disc is likely defective.

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.