Use the following table as reference:
Terminal
Name
Function
4 pipe system
2 pipe system
R
24VAC input
C
Common of AC input
WY
Hot water valve output
Pipe valve output
YA
Chilled water valve output
Auxiliary Heat (A)
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
