Lochinvar & A.O. Smith 100208502 Relay 340155-7024 this is a safety relief

this is a safety relief device designed only for emergency overpressure events

while the CCW rotation (lead end) matches original equipment specifications for single-phase

The 21L98 is the exact same component as the 21L9801

The HVAC air pressure sensor utilizes high-sensitivity diaphragms and normally open (N/O) silver-alloy contacts to provide reliable continuity and integrated safety logic

Use the range adjustment screw to set the opening point within the 70 to 260 PSI range while the system is operating under load

Lochinvar & A.O. Smith 100208502 Relay 340155-7024 this is a safety reliefThe Lochinvar & A. O. Smith 100208502 Relay is a high performance 1. 5HP pump relay kit engineered for precise load management in commercial and residential hydronic systems. As a critical OEM replacement part, this heavy duty relay ensures seamless electrical sequencing for 1. 5 horsepower circulation pumps, preventing motor lag and protecting the integrated control board from high amperage spikes. This component is widely utilized across the