Privacy Statement
Skip Ribbon Commands
Skip to main content


Three-port relays are used in HVAC systems, to perform a variety of relay functions, such as; transmit the higher of two input signals, lock out one pressure signal when a second signal is higher, or transmit the lower of two pressure signals.

Pneumatic Selector Relay


Pneumatic Selector Relay, transmits higher of two input pressures

Pneumatic  Selector Relay


Pneumatic selector relay for lockout, repeater and input pressure applications