York YCUL0055EE User Manual

JOHNSON CONTROLS
154
Form 150.63-NM9
Issue date: 5/20/2021
SECTION 9 – SERVICE AND TROUBLESHOOTING
Digital outputs
See the unit wiring diagram and Figure 44. The digital
outputs are located on TB7, TB8, and TB9 and TB-10
of the microboard. All outputs are 120 VAC with the
exception of TB8-6 to TB8-7 which are the contacts
that can be used for a remote evaporator pump start
signal. The voltage applied to either of these terminals
would be determined by field wiring.
Figure 44 - I/O Board Relay Contact Architecture
LD12722
SYS 1
COMP 1
TB7-2
SYS 1
COMP 2
TB7-4
SYS 1
COMP 3
TB7-5
TB7-3 LLSV 1
TB8-6
EVAP
PUMP
TB8-7
TB7
SYS 2
HGSV
TB10-7
SYS 2
FAN 2
TB10-8
TB10-9
TB10-10
SYS 2
FAN 4
TB10
TB8
TB10
SYS 2
COMPR 1 (4)
TB10-2
LLSV 2
TB10-3
SYS 2
COMPR 2 (5)
TB10-4
SYS 2
COMPR 3 (6)
TB10-5
TB7
SYS 1
HGSV
TB7-7
SYS 1
FAN 1
TB7-9
SYS 1
FAN 3
TB7-10
TB7-8
SYS 1
FAN 2
TB8-2
HEAT EXCH
HEATER
*
*
* Not Used
Each output is controlled by the microprocessor by
switching 120 VAC to the respective output connection
energizing contactors, evaporator heater, and solenoids
according to the operating sequence (see Figure 44).
120 VAC is supplied to the I/O board via connections
at TB7-1, TB7-6, TB10-1, TB10-6, TB8-1 and TB9-1.
Figure 44 illustrates the relay contact architecture on
the microboard.

York YCUL0055EE Specifications

General

Brand	York
Model	YCUL0055EE
Category	Heat Pump
Language	English