Blocked Vent Switch L300F | NBK-21056

NBK-21056 – Blocked Vent Switch L300F – Special Order

The NBK-21056 Blocked Vent Switch L300F is engineered to provide essential safety monitoring for furnaces, greenhouse heaters, and other HVAC systems. This switch is designed to detect blocked vent conditions that can lead to overheating or unsafe combustion, interrupting power if exhaust temperatures exceed 300°F (L300F) to protect your equipment and maintain safe operation.

⚠️ SPECIAL ORDER NOTICE: This is a special order item sourced from NBK, requiring 1–2 extra business days for processing.

Key Features:
✅ Critical Safety Component: Cuts off power at 300°F to prevent damage from blocked or restricted venting
✅ High-Temperature Operation: Suitable for systems where exhaust temperatures can rise under heavy load
✅ OEM-Equivalent Fit: Matches specifications for direct replacement of original blocked vent switches
✅ Durable Construction: Built to withstand high-heat environments for dependable protection

Specifications:
📌 SKU: 21056
📌 Category: Miscellaneous / Blocked Vent Switch
📌 Description: NBK-21056 Blocked Vent Switch L300F
📌 Trip Temperature: Opens at 300°F
📌 Equivalent To:

• Modine 4034100

• Modine 5H0730570005

• Modine 5H73057

Why Choose This Replacement:
Maintain the safety of your heating system by replacing failed or aged blocked vent switches, ensuring your unit will shut down if unsafe venting conditions occur.

Shipping & Availability:
This is a special order product from NBK, which typically adds 1–2 business days to standard processing.