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52C,P
SERIES
SERVICE TECHNICIAN GUIDE
PACKAGED TERMINAL AIR CONDITIONERS
AND HEAT PUMPS
Page
CONTENTS
HEATERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18,19
Page COMMON CAUSES OF HEATER FAILURE. . . . . . . 18
HEATER REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2,3
SUMMARY OF DANGERS, WARNINGS, OPERATING CONTROLS. . . . . . . . . . . . . . . . . . . . . 20-28
AND CAUTIONS .
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52C,P SERIES INTRODUCTION The focus of this manual is to provide basic information on service procedures, safety, troubleshooting, clean- ing, and component replacement for service techni- Potential hazards or unsafe practices which cians. It is intended for use only by HVAC service COULD result in minor personal injury or equip- technicians who have successfully completed ment damage. instruction and received Type I Certification from the U.S. Environmental Protection Agency. The instruc
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52 PQ A 3 12 3 0 1 AA Series Designation Chassis Options PTAC (Packaged Terminal Air Conditioner) Blank or AA – Standard CP – Corrosion Protection RC – Wall Thermostat Control CE – Cooling with Electric Heat RP – Wall Thermostat Control with CQ – Heat Pump with Electric Heat Corrosion Protection PC – Cooling Only PE – Cooling with Electric Heat PQ – Heat Pump with Electric Heat Latest Revision Packaging A – Z 1 – Domestic Electric Heater Size 0 – No Heating (Cooling Onl
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52C,P SERIES OPEN THE CONTROL BOX The control box is factory wired. To open the box, remove the 2 screws on the top of the control box and lower the front hinged panel. See Figure 6. REMOVE THE UNIT FROM THE WALL SLEEVE 1. Remove the four mounting screws that secure the PTAC unit to the wall sleeve (2 screws per side). See Figure 7. 2. Grasp the sides of the unit and slide it from the sleeve. NOTE: The mounting screws may be in a different location depending on brand of wall sleeve attac
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CONTROL BOX VARIOUS ATTACHMENT SCREWS HOLE LOCATIONS POWER CORD ACCESS COVER GE WALL SLEEVE AMANA, TRANE POWER HOLES (SLOTTED CORD HOLES) WALL SLEEVE HOLES FIGURE 6 — CONTROL BOX COVER CARRIER, BRYANT WALL SLEEVE HOLES FIGURE 7 — PTAC UNIT TO WALL SLEEVE MOUNTING SCREWS ACCESSING UNIT COMPONENTS ACCESSING THE HEATER ASSEMBLY — Once the ACCESSING INDOOR-AIR SECTION discharge deck assembly is removed, the Heater COMPONENTS Assembly should now be accessible. See Figure 10. REMOVE LATERAL
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52C,P SERIES END CAP PLENUM TOP LATERAL DUCT SCREWS (2) EXTENSION WALL RIGHT BRACKET LEFT BRACKET BRACKET SCREWS BRACKET SCREWS FIGURE 8 — PTAC UNIT WITH LATERAL DUCT ACCESSORY INSTALLED DISCHARGE DECK FIGURE 10 — ACCESSING HEATER PLATE ASSEMBLY ATTACHMENT SCREWS HEATER PLATE ASSEMBLY DISCHARGE DISCHARGE DECK SCREEN FIGURE 11 — REMOVAL OF HEATER FIGURE 9 — LOCATION OF ATTACHMENT PLATE ASSEMBLY SCREWS ON DISCHARGE DECK OF UNIT DETACH THE CONDENSER ORIFICE FROM THE d. Using Needle Nose Pli
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GUSSET GUSSET CONDENSER SCREWS ORIFICE (PLASTIC) FIGURE 14 — PRYING CONDENSER ORIFICE AWAY FROM TUBE SHEET PARTITION GUSSET GUSSET SCREWS FIGURE 12 — GUSSET REMOVAL CONDENSER ORIFICE CAPTIVE CAPTIVE SCREWS (2) SCREWS (2) FIGURE 15 — REMOVING TOP OF FIGURE 13 — LOCATION OF CAPTIVE SCREWS CONDENSER ORIFICE ON CONDENSER ORIFICE 7
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52C,P SERIES CONDENSER FAN OUTDOOR COIL TUBE SHEET SCREWS HUB CLAMP FIGURE 16 — LOCATION OF OUTDOOR COIL TUBE SHEET SCREWS FIGURE 18 — REMOVING CONDENSER FAN HUB CLAMP CONTROL DOOR SCREW SCREW HINGE PINS FRONT PANEL DISCHARGE (BACK VIEW) GRILLE FIGURE 19 — LOCATION OF SCREWS ON DISCHARGE GRILLE REINSTALL FRONT PANEL 1. Grasp the front panel firmly at the center of the top and bottom of the panel, tilting it forward 5 to 10 degrees from the vertical. See Figure 4. 2. Place the top of the fron
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GENERAL CLEANING Maintaining proper performance of 52C,P systems Consider the following safety issues before requires conscientious cleaning and care of compo- beginning: nents. See Figure 20. Specific components require periodic cleaning and/or replacement, including the New and unfamiliar tasks should be performed following: under the supervision of an experienced service technician. COMPONENT CLEANING SCHEDULE Personal protective equipment, such as safety Indoor Air Filter Monthly
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52C,P SERIES REPLACING THE INDOOR AIR FILTER — TOOLS NEEDED Remove the indoor air filter as detailed in Cleaning The following list includes the recommended tools, the Indoor Air Filter. If damaged, use a filter replace- devices, and cleaning solutions for use in cleaning the ment with the Carrier Part No. AIR-FILTER-10PK, 52C,P unit and components. available through Carrier Finished Goods and Carrier Replacement Component Division. Vacuum Cleaner with Crevice Tool Attachment, or Soft P
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SEASONAL CLEANING The indoor and outdoor coils should be cleaned at least once during every season. Refer to ACCESSING Do not set unit on end to drain water from basepan, UNIT COMPONENTS section to prepare unit. or at any other time. Oil will drain from the com- pressor sump, which could cause compressor failure. CLEANING THE INDOOR AND OUTDOOR COILS 6. Thoroughly clean the basepan and drain passages by rinsing with clean water. Be sure all debris is removed from the drain valve. See F
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52C,P SERIES FIGURE 23 — PTAC EXTERIOR SURFACES FIGURE 25 — CLEANING COILS FIGURE 24 — VACUUMING EVAPORATOR COIL DRAIN VALVE FIGURE 26 — BASEPAN SECTION 12
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COMPRESSOR A cutaway view of the rotary compressor with key pump bearing provides a thrust surface for the shaft components labeled is shown in Figure 27. The motor and the rolling piston. Compressed gas is separated stator is rigidly attached to the compressor shell. The from the suction gas by the vane. Discharge gas pres- rotor is pressed onto the eccentric shaft, which is sup- sure and the vane spring keep the vane in contact with ported by 2 bearings. Both the discharge valve and dis- th
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52C,P SERIES The rotary compression process (Figure 28), starts at BASIC HERMETIC COMPRESSOR top dead center as shown in (1). Suction gas flows ELECTRICAL MEASUREMENTS through the suction inlet and into the cylinder area. There are 2 basic electrical tests for hermetic compres- As the shaft rotates through 90 degrees, the rolling sors that will determine the electrical state of the piston moves to position A as shown in (2). The suction motor. The first test requires checking the electric
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SYMPTOM Compressor Compressor Compressor Compressor Compressor Starts and Starts After Will Not POSSIBLE CAUSE Will Not Start Cycles Off Runs But Cycling the Start. It Hums and Makes No (Not On Cycles On the Overload and Cycles On Noise Overload) Overload Several Times the Overload COILS/FILTERS DIRTY OR PLUGGED X AIR OR NONCONDENSABLE GASES XX IN SYSTEM SYSTEM REFRIGERANT OVERCHARGED X X DISCHARGE LINE RESTRICTED XX CAPILLARY TUBE OR STRAINER XX X RESTRICTED OR PLUGGED FAN BLADE OR MOTOR DEFECT
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52C,P SERIES REMOVING THE COMPRESSOR — Follow the steps below to remove the compressor: 1. Disconnect all power to unit. 2. Remove unit from wall sleeve as detailed in the UNIT DISASSEMBLY section. The unit weighs up to 150 pounds. Seek assistance or use a lifting device when removing unit from wall sleeve. 3. If the unit is a heat pump: Disconnect the wire plug on the reversing valve solenoid and carefully remove the outdoor thermostat capillary from the outdoor coil. See Figure 32. 4
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12. Install the new compressor and the new capillary assembly (the correct capillary and strainer may be obtained from Carrier RCD), into the unit. 13. Leak check the unit with 150 psi of nitrogen pressure. 14. For 52C,P units, the system should be evacuated from the high side to the low side to a minimum of 200 microns of mercury. This evacuation removes residual moisture from the system prior to charging. 15. For Heat Pump Units: Recharge unit to the nameplate refrigerant charge using
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52C,P SERIES HEATERS The heater in 52C,P units is located directly behind COMMON CAUSES OF the evaporator coil. The heater assembly includes the HEATER FAILURE heater (2.3 kW, 3.4 kW or 5 kW), a primary limit Heater failure may result from broken heater coils, switch, and a secondary limit switch. See Figure 34. primary limit switch failure, or an open secondary The primary and secondary limit switches are safety limit switch. These conditions are generally caused by switches that regul
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TOOLS NEEDED — The following list includes rec- Coil resistance must also be checked to verify the ommended tools and devices for working on the heater heater is operating correctly. The resistance of the section of 52C,P units. heater coils must meet approximate levels for the heater to perform at its optimum efficiency. See Phillips Head Screw Driver Figure 36 for approximate resistance for heaters at Needle Nose Pliers 75 F. Before checking the heater coil resistance, be Volt-ohmmete
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52C,P SERIES OPERATING CONTROLS The 52C,P heat pump unit contains all the compo- UNIT-MOUNTED CONTROLS nents of the heat/cool and cooling only unit, and the The controls and components used in the 52C,P cool- following additional ones: the outdoor frost thermostat ing only or heat/cool units are as follows: the selec- and the reversing valve. The outdoor frost thermostat tor switch, the indoor thermostat, the dual capacitor, prevents operation of the unit in the heat pump mode the temperatu