The Lochinvar air pressure switch is designed for compatible heater applications where pressure-based airflow monitoring is needed. An air pressure switch is useful because it helps verify proper operating conditions, supporting safer and more dependable heater performance during operation.This replacement is especially useful when the original switch is failing, inaccurate, damaged, or no longer activating correctly. Including mounting nuts helps support cleaner installation and dependable retention.The 100166258 is a practical service part when a compatible Lochinvar heater needs an air pressure switch to restore dependable monitoring support. Lochinvar air pressure switch Includes mounting nuts Designed for compatible heater applications Useful when the original switch is inaccurate or failing Supports cleaner and more dependable heater performance