50ZHA024-060
Packaged Heat Pump Units
Installation, Start-Up and Service Instructions
NOTE:
Read the entire instruction manual before starting the
installation.
TABLE OF CONTENTS
SAFETY CONSIDERATIONS .....................................................1
INTRODUCTION ..........................................................................2
RECEIVING AND INSTALLATION ..........................................2
Check Equipment......................................................................2
IDENTIFY UNIT ................................................................2
INSPECT SHIPMENT ........................................................2
Provide Unit Support ................................................................2
SLAB MOUNT ...................................................................2
GROUND MOUNT ............................................................2
Provide Clearances....................................................................2
Place Unit..................................................................................2
Select and Install Ductwork .....................................................2
CONVERTING
HORIZONTAL
DISCHARGE
UNITS TO DOWNFLOW (VERTICAL) DIS-
CHARGE ..................................................................4
Provide for Condensate Disposal .............................................4
Install Electrical Connections...................................................5
HIGH-VOLTAGE CONNECTIONS..................................5
ROUTING POWER LEADS INTO UNIT ........................6
CONNECTING GROUND LEAD TO UNIT GROUND .6
ROUTING CONTROL POWER WIRES ..........................6
ACCESSORY ELECTRIC HEAT WIRING .....................6
PRE-START-UP ............................................................................6
START-UP .....................................................................................7
Check for Refrigerant Leaks ....................................................8
LOCATE AND REPAIR REFRIGERANT LEAKS AND
CHARGE THE UNIT AS FOLLOWS: .............................8
Start-Up Cooling Section and Make Adjustments ..................8
CHECKING COOLING CONTROL OPERATION .........8
Refrigerant Charge....................................................................8
NO CHARGE ......................................................................8
LOW CHARGE COOLING ...............................................9
HEATING MODE CHARGE.............................................9
Indoor Airflow and Airflow Adjustments................................9
FOR 208/230-V .................................................................13
Unit Controls...........................................................................13
HIGH-PRESSURE RELIEF VALVE...............................13
LOSS OF CHARGE SWITCH.........................................13
COMPRESSOR OVERLOAD..........................................13
Sequence of Operation............................................................13
FAN OPERATION............................................................13
COOLING..........................................................................14
HEATING..........................................................................14
CONTINUOUS FAN ........................................................14
DEFROST..........................................................................14
ELECTRIC RESISTANCE HEATING............................14
MAINTENANCE.........................................................................15
Air Filter..................................................................................15
Unit Top Removal (Outdoor-Coil Side) ................................15
Indoor Blower and Motor.......................................................15
Outdoor Coil, Indoor Coil, and Condensate Drain Pan ........16
Outdoor Fan ............................................................................16
Electrical Controls and Wiring...............................................16
Refrigerant Circuit ..................................................................17
Indoor Airflow ........................................................................17
Metering Devices ....................................................................17
Lubrication ..............................................................................17
Liquid Line Strainer................................................................17
High Flow Valves...................................................................17
TROUBLESHOOTING ...............................................................17
START-UP CHECKLIST............................................................17
NOTE TO INSTALLER—Before installation, READ THESE
INSTRUCTIONS CAREFULLY AND COMPLETELY. Also,
make sure the User’s Manual and Replacement Guide are left with
the unit after installation.
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can be
hazardous due to system pressure and electrical components. Only
trained and qualified workers should install, repair, or service
air-conditioning equipment.
Untrained workers can perform basic maintenance functions of
cleaning coils and filters. All other operations should be performed
by trained service people. When working on air-conditioning
equipment, pay attention to precautions in the literature, tags, and
labels attached to the unit, and other safety precautions that may
apply.
Fig. 1—Unit 50ZHA
A05194
Visit www.carrier.com
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1
4
Tab
6 8
PC 101
Printed in U.S.A.
Catalog No. 50ZHA-1SI
Pg 1
9-05
Replaces: New
