This Lochinvar Pressure Switch is a safety device designed to monitor the pressure within the system. It operates by opening or closing an electrical circuit when a certain pressure level is reached, either too high or too low. The switch is typically used in heating, ventilation, and air conditioning (HVAC) systems to prevent damage or failure due to improper pressure levels. It features a Single Pole Double Throw (SPDT) configuration, which allows it to control one circuit and switch between two routes. The product is made from durable materials for long-lasting use and reliable performance.