Picture of Anthony Coker

Anthony Coker

Technical Services Manager North Georgia District

Simplified Wiring Guide for R, Y1, Y2 Terminals

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R Terminal

24VAC TRANSFORMER1
UCB Main Pin1
UCB Unit Shutdown Smoke Shutdown A 24VAC OUT
UCB Unit Shutdown Smoke Shutdown B
UCB Unit Shutdown Remote Shutdown A
UCB Unit Shutdown Remote Shutdown B
UCB PMR 24V A
UCB PMR Cont B
UCB Main Pin7
LSM
UCB Main Pin8
R Terminal (You Now have R)

Y1 Terminal

UCB THERMOSTAT Y1 TERMINAL
UCB ECON Pin1 Blue to
PL6 Pin2 Blue Loop Plug
PL6-R Pin2 Blue Loop Plug
PL6-R Pin5 Blue Loop Plug
PL6 Pin5 Gray Loop Plug
UCB ECON Pin2 Gray
UCB REHEAT/HP Pin1 Gray
REHEAT CONTROL Pin6 Gray
REHEAT CONTROL Pin5 Gray*
UCB REHEAT/HP Pin2 Gray*
UCB COMP Pin2 and
UCB to LPS1 to
UCB HPS1 to
UCB Comp Pin3 to
FTP to
COFS to
CC Compressor Contactor
Y1 Terminal (You now have Y1)

Y2 Terminal

UCB THERMOSTAT Y2 TERMINAL
UCB ECON Pin4 Yellow to
PL6 Pin8 Yellow Loop Plug
PL6-r Pin8 Yellow Loop Plug
PL6-R PIn9 Yellow Loop Plug
PL6 Pin9 Orange Loop Plug
UCB ECON Pin3
UCB REHEAT/HP Pin3 Orange
REHEAT CONTROL Pin11 Orange
REHEAT CONTROL Pin10 Orange*
UCB REHEAT/HP Pin4 Orange*
UCB COMP Pin1
LDR (LOADER)
Y2 Terminal (You now have Y2)

The next series will show W1, W2 and Reheat! In various configurations, like UCB, CTB etc…

The link to wiring diagram above shows color paths for colors above and two diagrams one for Siemens economizer and Honeywell (Jade) W7220 control on the other diagram.

Disclaimer: The technical statements, information and recommendations contained herein are believed to be accurate as of the date hereof, but Mingledorff’s does not make representations or warranties, express or implied, as to its accuracy, its completeness, or the results to be obtained. The information is being provided for informational purposes only and is intended for use by persons having adequate skill and expertise regarding the proper selection, use and application of the products and recommendations and at their own risk and discretion. 

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