Salus ST101ZB Quick Start Manual page 5

Use the following table as reference:
Terminal
Name
4 pipe system
R 24VAC input
C Common of AC input
WY Hot water valve output
YA Chilled water valve output
Gl Fan coil low speed control
Gm Fan coil medium speed control
Gh Fan coil high speed control
Ac Accessory output (relay contact)
Ac Accessory output (other side of relay)
Tp Pipe temperature sensor input
Tx External temperature sensor input
Ts Setback contact input
Tc Tx/Tp/Ts common
Function
2 pipe system
Pipe valve output
Auxiliary Heat (A)