Allied 4SCU23LX Service Manual

SERVICE MANUAL
4SCU23LX
This is a safety alert symbol and should never be ignored. When you see this symbol on labels or in manuals, be alert to
the potential for personal injury or death.
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a licensed professional HVAC installer or
equivalent, service agency, or the gas supplier.
To prevent serious injury or death:
Lock-out/tag-out before performing maintenance.
If system power is required (e.g., smoke detector
maintenance), disable power to blower, remove fan
belt where applicable, and ensure all controllers
and thermostats are set to the "OFF" position before
performing maintenance.
Always keep hands, hair, clothing, jewelry, tools, etc.
away from moving parts.
508380-01
WARNING
WARNING

Table of Contents

Technical Specifications ..............................................2
Typical Unit Parts Arrangement ...................................5
General Information .....................................................8
Operating Gauge Set and Service Valves ...................8
Installation ...................................................................9
New or Replacement Line Set ...................................11
Electrical - Circuit Sizing and Wire Routing ...............22
Thermostat Control and Low Voltage Control Wiring 22
Outdoor Unitary Control.............................................27
Unit Operation ...........................................................28
Servicing Units Delivered Void of Charge..................31
Start-Up .....................................................................31
System Operation and Service ..................................32
Unit Selection Code for Outdoor Control ...................48
Configuring Unit .........................................................52
System Overview.......................................................53
Maintenance ..............................................................54
Unit Wiring Diagram ..................................................55
Unit Sequence of Operation ......................................56
Component Testing ....................................................59
System Refrigerant ....................................................93
Charge Mode Jumper ................................................93
This unit must be matched with an indoor coil as
specified with AHRI. For AHRI Certified system match-
ups and expanded ratings, visit www.AHRIdirectory.
org. Coils previously charged with HCFC-22 must be
flushed.
*P508380-01*
Issue 2309
IMPORTANT
(P) 508380-01
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