Functional Devices RIB RIB2421SB Relay This is an automatic reset

This is an automatic reset switch

For the service tech

Why is my contactor humming or buzzing

This high-efficiency burner is the direct replacement for 301210

corrosion-protected steel enclosure that meets UL 1995 plenum requirements

Functional Devices RIB RIB2421SB Relay This is an automatic resetThe Functional Devices RIB2421SB is a heavy duty, pre packaged 20 Amp enclosed relay engineered for high demand HVACR and industrial energy management systems. This SPDT relay features a multi voltage coil that accepts 24VAC DC, 120VAC, and 208 277VAC, providing a versatile solution for varying control circuit requirements without the need for multiple stocked parts. Designed for direct BAS and lighting control, the RIB2421SB relay includes an