SErvice Manual

ManualsBrandsAirQuest ManualsAir Conditioner Condensers2 Ton 14 SEER Air Conditioner Condenser

421 08 5400 03 9/19/2017

APPLICATION GUIDELINE &

SERVICE MANUAL

R- 410A & R- 22 Split System AC & HP

TABLE OF CONTENTS

PAGE

UNIT IDENTIFICATION 3.............................

SAFETY CONSIDERATIONS 6........................

INTRODUCTION 6...................................

INSTALLATION GUIDELINE 6.........................

Residential New Construction 6.....................

Add- On Replacement (Retrofit) - R- 22 to R- 410A 6...

Seacoast 6.......................................

LOW- AMBIENT COOLING GUIDELINE 6...............

LONG LINE GUIDELINE 7............................

ACCESSORY DESCRIPTIONS 7......................

CABINET ASSEMBLY 7..............................

Labeling 8.......................................

ELECTRICAL 9......................................

Aluminum Wire 9..................................

Contactor 9......................................

Capacitor 9......................................

Cycle Protector 10................................

Crankcase Heater 10..............................

Time- Delay Relay (TDR) 11........................

Pressure Switches 11..............................

Defrost Thermostat 12.............................

Defrost Control Boards 12..........................

FAST # 1173636 / 1177927 /

1190281 DEFROST CONTROL 12..................

DEFROST CONTROL (Fast # 1174185) 14...........

System function and Sequence of operation

(Fast # 1174185) 15...............................

Troubleshooting (Fast # 1174185) 15................

FAST# 1185790 DEFROST CONTROL 16............

Quiet Shift- 2 (non- communicating) 16...............

ECM Fan Motor (single stage equipment) 16..........

PSC Fan Motor 16................................

Compressor Plug 17...............................

Low- Voltage Terminals 17..........................

COPELAND SCROLL COMPRESSOR 17...........

LG SCROLL COMPRESSOR 18....................

Characteristics of the LG Scroll Compressor: 18.......

COMPRESSOR TROUBLESHOOTING 19...........

Compressor Failures 19............................

Mechanical Failures 19............................

PAGE

REFRIGERATION SYSTEM 22........................

Refrigerant 22....................................

Servicing Systems on Roofs With Synthetic Materials 22

Brazing 22.......................................

Service Valves and Pumpdown 22..................

Liquid Line Filter Drier 24...........................

Suction Line Filter Drier 25.........................

Accumulator 25...................................

Thermostatic Expansion Valve (TXV) 26..............

MAKE PIPING CONNECTIONS 27.....................

REFRIGERATION SYSTEM REPAIR 28.................

Leak Detection 28.................................

Coil Removal 28..................................

Compressor Removal and Replacement 29...........

System Clean- Up After Burnout 29..................

Evacuation 30....................................

TROUBLESHOOTING WITH SUPERHEAT 30...........

TWO STAGE NON- COMMUNICATING N4A7/N4H6 40...

Operating Ambient 40..............................

Airflow Selections (ECM Furnaces) 40...............

Airflow Selection for Variable Speed

Furnaces (non- communicating) 40..................

Airflow Selection for FVM4X Fan Coils

(non- communicating) 40...........................

SYSTEM FUNCTION AND SEQUENCE OF OPERATION

(N4A7/N4H6) 40.....................................

Cooling 40.......................................

Heating 40.......................................

Compressor Operation 41..........................

Quiet Shift 41.....................................

Quiet Shift- 2 (non- communicating) 41...............

Defrost 41........................................

Defrost Speedup 41...............................

CHECK CHARGE 41.................................

SINGLE- STAGE AC (*SA5, *SA6) GENERAL SEQUENCE

OF OPERATION - STANDARD THERMOSTAT 42........

AC CONTROL FUNCTIONS AND SEQUENCE OF

OPERATION 42......................................

SINGLE- STAGE HEAT PUMP (*SH4, *SH5, *SH6)

GENERAL SEQUENCE OF OPERATION - STANDARD

THERMOSTAT 43....................................

HEAT PUMP SYSTEM FUNCTIONS AND SEQUENCE OF

OPERATION 43......................................

Summary of content (66 pages)

PAGE 1
APPLICATION GUIDELINE & SERVICE MANUAL R- 410A & R- 22 Split System AC & HP TABLE OF CONTENTS PAGE PAGE UNIT IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 REFRIGERATION SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . 22 UNIT IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Refrigerant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . .
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TROUBLESHOOTING (SINGLE- STAGE) . . . . . . . . . . . . . 46 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 TWO- STAGE *CA7, *CA9, *CH6, *CH9 . . . . . . . . . . . . . . 52 Troubleshooting circuit board FAST # 1185237, 1186140 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Application Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Model Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PAGE 3
UNIT IDENTIFICATION system malfunctions. This section explains how to obtain the model and serial number from the unit rating plate. These numbers are needed to service and repair the R- 410A and R- 22 air conditioner or heat pump. Model and serial numbers can be found on unit rating plate. Troubleshooting Charts for Air Conditioners and Heat Pumps are provided in the appendix at back of this manual.
PAGE 4
OUTDOOR UNIT MODEL NUMBER IDENTIFICATION GUIDE (single phase) Digit Position: 1 2 3 4 5, 6 7 8 9 10 11 12 Example Part Number: * C A 9 24 G K A 2 0 0 * = Mainline BRANDING C = Two stage communicating KEY S = Single stage CHARACTERISTIC communicating A = Air Conditioner TYPE H = Heat Pump 5 = 15 SEER 6 = 16 SEER 7 = 17 SEER 8 = 18 SEER NOMINAL EFFICIENCY 9 = 19 SEER 24 = 24,000 BTUH = 2 tons 36 = 36,000 BTUH = 3 tons 48 = 48,000 BTUH = 4 tons NOMINAL CAPACITY 60 = 60,000 BTUH = 5 tons
PAGE 5
OUTDOOR UNIT MODEL NUMBER IDENTIFICATION GUIDE (single phase) Digit Position: 1,2 3 4 5,6 7 8 9 10 11 Example Part Number: WC A 5 24 4 G K A 1 WC = Condensing Unit A = Air Conditioner H = Heat Pump 3 = 13 SEER 4 = 14 SEER 5 = 15 SEER 18 = 18,000 BTUH = 1½ tons 24 = 24,000 BTUH = 2 tons 30 = 30,000 BTUH = 2½ tons 36 = 36,000 BTUH = 3 tons 42 = 42,000 BTUH = 3½ tons 48 = 48,000 BTUH = 4 tons 60 = 60,000 BTUH = 5 tons TYPE SEER NOMINAL CAPACITY 4 = R- 410A A = Standard Grille G = Coil G
PAGE 6
SAFETY CONSIDERATIONS Installation, service, and repair of these units should be attempted only by trained service technicians familiar with standard service instruction and training material. All equipment should be installed in accordance with accepted practices and unit Installation Instructions, and in compliance with all national and local codes. Power should be turned off when servicing or repairing electrical components.
PAGE 7
LONG LINE GUIDELINE Refer to Split System Long Line Applications Guidelines for air conditioner and heat pump systems. ACCESSORY DESCRIPTIONS See the appropriate specification sheets and installation manuals for accessory information. CABINET ASSEMBLY Access Compressor Or Other Internal Cabinet Components NOTE: It is not necessary to remove the top cover to gain access. Removing the top cover may cause grill panels, corner posts or coils to be damaged.
PAGE 8
Fig. 2 – Typical HP Control Box Labeling Fig.
PAGE 9
ELECTRICAL ! 2. With power off, use ohmmeter to check for continuity of coil. Disconnect leads before checking. A low resistance reading is normal. Do not look for a specific value, as different part numbers will have different resistance values. 3. Reconnect leads and apply low- voltage power to contactor coil. This may be done by leaving high- voltage power to outdoor unit off and turning thermostat to cooling. Check voltage at coil with voltmeter. Reading should be between 20v and 30v.
PAGE 10
2. Capacitance testers are available which will read value of capacitor. If value is not within 10 percent value stated on capacitor, it should be replaced. If capacitor is not open or shorted, the capacitance value is calculated by measuring voltage across capacitor and current it draws. ! WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death. Exercise extreme caution when taking readings while power is on.
PAGE 11
NOTE: Because these switches are attached to refrigeration system under pressure, it is not advisable to remove this device for troubleshooting unless you are reasonably certain that a problem exists. If switch must be removed, remove and recover all system charge so that pressure gauges read 0 psi. Never open system without breaking vacuum with dry nitrogen.
PAGE 12
To replace switch: 1. Apply heat with torch to solder joint and remove switch. ! CAUTION PERSONAL INJURY HAZARD Failure to follow this caution may result in personal injury. Wear safety glasses when using torch. Have quenching cloth available. Oil vapor in line may ignite when switch is removed. 2. Braze in 1/4- in. flare fitting and replace pressure switch.
PAGE 13
1190281 board for ECM motors A150020 Fig. 8 – FAST # 1173636 / 1177927 / 1190281 Defrost Control Troubleshooting (FAST # 1173636 / 1177927 / 1190281) If outdoor unit will not run: 1. Does the Y input has 24 volts from thermostat? If not, check thermostat or wire. If yes proceed to #2 2. The Y spade terminal on the circuit board should have 24 volts if Y input is energized. This output goes through the pressure switches and to the contactor.
PAGE 14
To fully troubleshoot defrost thermostat and control function (FAST # 1173636 / 1177927 / 1190281): 1. Turn thermostat to OFF. Shut off all power to outdoor unit. 2. Remove control box cover for access to electrical components and defrost control board. 3. Disconnect defrost thermostat leads from control board, and connect to ohmmeter. Thermostat leads are black, insulated wires connected to DFT and R terminals on control board.
PAGE 15
OF1 DFT OF2 T2 C C O T1 Y O R W2 Y C P1 120 60 30 P3 ON DFT QUIET SHIFT 90 INTERVAL TIMER OFF 30 60 J1 SPEEDUP Speedup Pins HK32EA003 Quiet Shift Defrost interval DIP switches A05378 Fig. 9 – 1174185 Defrost Control Quiet Shift (Fast # 1174185) This control has the option of shutting down the compressor for 30 seconds going in and coming out of defrost. This is accomplished by turning DIP switch 3 to the ON position. Factory default is in the OFF position.
PAGE 16
3. If unit still will not run defrost, remove thermostat pigtail harness from board and perform checks directly on input pins with jumper wires. The pigtail may have a bad connection or be mis- wired. FAST# 1185790 DEFROST CONTROL This defrost control is used in most non- communicating Performance Series heat pumps with R- 410A refrigerant and has all the same functionality, speedups, troubleshooting as the FAST# 1174185 except for the forced defrost timing when Quiet Shift- 2 is enabled.
PAGE 17
The bearings are permanently lubricated; therefore, no oil ports are provided. For suspected electrical failures, check for loose or faulty electrical connections, or defective fan motor capacitor. The fan motor is equipped with a thermal overload device in the motor windings which may open under adverse operating conditions. Allow time for the motor to cool so the device can reset. Further checking of the motor can be done with an ohmmeter.
PAGE 18
LG SCROLL COMPRESSOR The compressors used in these products are specifically designed to operate with designated refrigerants and cannot be interchanged. LG produced scroll compressors are designed to operate and function as the typical orbiting scroll on a fixed scroll design. Refrigerant flow and compression is basically the same.
PAGE 19
A12344 4. Slide out the sensor, slide in replacement and reinstall the cover A12345 COMPRESSOR TROUBLESHOOTING Compressor Failures Compressor failures are classified in 2 broad failure categories; mechanical and electrical. Both types are discussed below. Mechanical Failures A compressor is a mechanical pump driven by an electric motor contained in a welded or hermetic shell. In a mechanical failure, motor or electrical circuit appears normal, but compressor does not function normally.
PAGE 20
6. 7. 8. 9. remedied with a field installed discharge muffler. Recommend loop by continuous tubing with no more than 12 inches vertical and 6 inch horizontal loop. An internal “thunking”, “thumping”, “grinding” or “rattling” noise could indicate compressor internal failures and may be verified by comparing the compressor amperage to what the compressor should be drawing according to a manufacturer’s performance data.
PAGE 21
Single- Phase Motors To identify terminals C, S, and R: 1. Turn off all unit power. 2. Discharge run and start capacitors to prevent shock. 3. Remove all wires from motor terminals. 4. Read resistance between all pairs of terminals using an ohmmeter on 0- 10 ohm scale. 5. Determine 2 terminals that provide greatest resistance reading. Through elimination, remaining terminal must be common (C). Greatest resistance between common (C) and another terminal indicates the start winding because it has more turns.
PAGE 22
REFRIGERATION SYSTEM 3. Place terry cloth shop towel inside unit immediately under component(s) to be serviced and prevent lubricant run- offs through the louvered openings in the base pan. 4. Perform required service. 5. Remove and dispose of any oil contaminated material per local codes. Refrigerant ! WARNING UNIT OPERATION AND SAFETY HAZARD Failure to follow this warning could result in personal injury or equipment damage.
PAGE 23
tube. This tube must be installed on the liquid service valve. After connecting the stub tube to the liquid service valve of a heat pump, the valves are ready for brazing. The interconnecting tubing (line set) can be brazed to the service valves using industry accepted methods and materials. Consult local codes.
PAGE 24
future use. Because defective valve is not overheated, it can be analyzed for cause of failure when it is returned. 3. Braze new valve onto used stubs. Keep stubs oriented correctly. Scratch corresponding matching marks on old valve and stubs and on new valve body to aid in lining up new valve properly. When brazing stubs into valve, protect valve body with wet rag to prevent overheating. 4. Use slip couplings to install new valve with stubs back into system.
PAGE 25
Install Liquid- line Filter Drier Indoor - AC CAUTION ! UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage or improper operation. To avoid performance loss and compressor failure, installation of filter drier in liquid line is required. ! CAUTION UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage or improper operation. To avoid filter drier damage while brazing, filter drier must be wrapped in a heat- sinking material such as a wet cloth.
PAGE 26
6. Scratch matching marks on tubing studs and old accumulator. Scratch matching marks on new accumulator. Unbraze stubs from old accumulator and braze into new accumulator. 7. Thoroughly rinse any flux residue from joints and paint with corrosion- resistant coating such as zinc- rich paint. 8. Install factory authorized accumulator into system with copper slip couplings. 9. Evacuate and charge system. Pour and measure oil quantity (if any) from old accumulator.
PAGE 27
3. Remove TXV support clamp using a 5/16- in. nut driver. Save the clamp (N coils only). 7. Connect equalizer tube of TXV to 1/4- in. equalizer fitting on vapor line adapter. 8. Attach TXV bulb to horizontal section of suction line using clamps provided. Insulate bulb with field- supplied insulation tape. See Fig. 23 for correct positioning of sensing bulb. 9. Proceed with remainder of unit installation. 4. Remove TXV using a backup wrench on connections to prevent damage to tubing. 5.
PAGE 28
CAUTION ! UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage or improper operation. If ANY refrigerant tubing is buried, provide a 6 in. vertical rise at service valve. Refrigerant tubing lengths up to 36 in. may be buried without further special consideration. Do not bury lines longer than 36 in.
PAGE 29
! WARNING ! CAUTION FIRE HAZARD UNIT DAMAGE HAZARD Failure to follow this warning could result in personal injury or equipment damage. Failure to follow this caution may result in equipment damage or improper operation. Cut tubing to reduce possibility of personal injury and fire. Do not leave system open to atmosphere. Compressor oil is highly susceptible to moisture absorption. 8. Use a small tubing cutter to cut the liquid and vapor lines at both sides of coil.
PAGE 30
Evacuation MICRONS Proper evacuation of the system will remove non- condensibles and assure a tight, dry system before charging. The two methods used to evacuate a system are the deep vacuum method and the triple evacuation method. Deep Vacuum Method The deep vacuum method requires a vacuum pump capable of pulling a vacuum of 500 microns and a vacuum gauge capable of accurately measuring this vacuum depth. The deep vacuum method is the most positive way of assuring a system is free of air and moisture.
PAGE 31
16. R- 410A Systems: Make sure proper valve is used (Not R- 22) If OK proceed to Step 2 2. Check superheat at vapor service valve and Pseudo Evaporator Superheat. S S S If OK proceed to Step 17 17. Check for even temperature distribution at outlet of each circuit of evaporator If both are less than 2F, TXV likely not controlling properly, i.e. stuck open - > REPLACE VALVE S If OK proceed to Step 18 18.
PAGE 32
valve pressure and evaporator outlet temperature to calculate superheat 4. Determine suction line pressure drop from Table 5 (R- 410A) or Table 6 (R- 22). 5. Calculate Pseudo Evaporator Superheat. Add the suction line pressure drop to the pressure reading obtained at suction service valve.
PAGE 33
line. Based on Table 5, the system has approximately 3- psig pressure drop in the vapor line. Per the instructions, he takes the suction line temperature at the outlet of the evaporator and finds it to be 53F. Tom adds 3 psig to the 125- psig suction pressure at the outdoor unit to get 128 psig evaporator pressure. The saturated pressure of 128 equates to 44F. Tom calculates the evaporator superheat to be (53F - 44F =) 9F. The TXV appears to be operating properly.
PAGE 34
Fig. 30 – Pseudo Evaporator Superheat Pressure and Temperature Measurement Locations Table 7—R- 410A Refrigerant Pressure Temperature Chart PSIG 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 100 102 104 106 108 110 112 114 116 F - 38.2 - 35.3 - 32.5 - 29.9 - 27.3 - 24.9 - 22.6 - 20.4 - 18.3 - 16.2 - 14.2 - 12.3 - 10.4 - 8.6 - 6.9 - 5.1 - 3.5 - 1.9 - 0.3 1.3 2.8 4.2 5.7 7.1 8.5 9.8 11.1 12.4 13.7 15.0 16.2 17.4 18.6 19.
PAGE 35
Table 8—R- 22 Refrigerant Pressure Temperature Relationship psig 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 F - 25.9 - 24.0 - 22.1 - 20.4 - 18.7 - 17.0 - 15.4 - 13.8 - 12.3 - 10.8 - 9.3 - 7.9 - 6.5 - 5.2 - 3.9 - 2.6 - 1.3 0.0 1.2 2.4 3.6 4.7 5.8 6.9 8.0 9.1 10.2 11.2 12.2 13.2 14.2 15.2 16.2 17.1 18.1 19.0 19.9 20.8 21.7 22.6 23.5 24.3 25.2 26.0 26.8 27.6 28.
PAGE 36
Table 9—R- 410A Subcooling Chart Liquid Line Temperature (_F) Liq Press (psig) P- T (_F) 200 70 2 68 4 66 6 64 8 62 10 60 12 58 14 56 16 54 18 52 20 50 210 73 71 69 67 65 63 61 59 57 55 53 220 76 74 72 70 68 66 64 62 60 58 56 230 79 77 75 73 71 69 67 65 63 61 59 240 82 80 78 76 74 72 70 68 66 64 62 250 84 82 80 78 76 74 72 70 68 66 64 260 87 85 83 81 79 77 75 73 71 69 67 270 89 87 85 83 81 79 77 75 73 71 69 280
PAGE 37
Table 10—R- 410A Superheat Chart Vapor Line Temperature (F) Vap Press (psig) 80 82 84 86 88 90 92 94 96 98 100 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 132 134 136 138 140 142 144 146 148 150 152 154 156 158 160 162 P- T (F) 21 22 23 24 25 26 27 29 30 31 32 33 34 35 35 36 37 38 39 40 41 42 43 44 44 45 46 47 48 48 49 50 51 52 52 53 54 55 55 56 57 58 2 23 24 25 26 27 28 29 31 32 33 34 35 36 37 37 38 39 40 41 42 43 44 45 46 46 47 48 49 50 50 51 52 53 54 54 55 56 57 57 58 59 60 4 25 26 2
PAGE 38
Table 11—R- 22 Subcooling Chart R- 22 Liquid Line Temperature (_F) Liquid Pres (psig) PT (F) 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 295 300 305 310 315 320 325 330 70 72 74 76 79 81 83 85 87 89 91 93 95 96 98 100 102 103 105 107 108 110 111 113 114 116 117 119 120 121 123 124 126 127 128 129 131 132 133 135 136 137 138 Subcooling (_F) 2 68 70 72 74 77 79 81 83 85 87 89 91 93 94 96 98 100 101 103 105 1
PAGE 39
Table 12—R- 22 Superheat Chart R- 22 Vapor Line Temperature (_F) Vapor Press (psig) PT (F) 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 26 27 28 28 29 30 31 32 32 33 34 35 35 36 37 38 38 39 40 40 41 42 42 43 44 44 45 46 46 47 48 48 49 50 50 51 51 52 53 53 54 54 55 Superheat (_F) 2 28 29 30 30 31 32 33 34 34 35 36 37 37 38 39 40 40 41 42 42 43 44 44 45 46 46 47 48 48 49 50 50 51 52 52 53 53 54 55 55 56 56 57 4 30 31 32
PAGE 40
TWO STAGE NON- COMMUNICATING N4A7/N4H6 most closely matches the required airflow shown in the air conditioning Product Data for HIGH speed. 3. The CF DIP switch setting determines airflow during low stage cooling operation. Select the CF DIP switch setting corresponding to the available airflow shown in the furnace installation instructions that most closely matches the required airflow shown in the air conditioning Product Data for LOW speed.
PAGE 41
begins counting. Compressor will not come on until this delay expires. In the event of a power interruption, the time guard will not allow another cycle for 5 minutes. Compressor Operation The basic scroll design has been modified with the addition of an internal unloading mechanism that opens a by- pass port in the first compression pocket, effectively reducing the displacement of the scroll. The opening and closing of the by- pass port is controlled by an internal electrically operated solenoid.
PAGE 42
For standard refrigerant line lengths (80 ft/24.38 m or less), allow system to operate in cooling mode at least 15 minutes. If conditions are favorable, check system charge by subcooling method. If any adjustment is necessary, adjust charge slowly and allow system to operate for 15 minutes to stabilize before declaring a properly charged system. If the indoor temperature is above 80_F /26.
PAGE 43
F o r lo w a m b ie n t c o o lin g w ith th e O b s e rv e r Communicating Wall Control the cooling lockout must be set to “Off” in the Wall Control setup. Liquid Line Solenoid When operating in communicating mode the standard thermostat terminals will not function. A terminal on the non- communicating thermostat bus labeled “LS” on the AC control board is provided for wiring liquid line solenoids when in communicating mode.
PAGE 44
S One minute time delay of outdoor fan at termination of cooling mode when outdoor ambient is greater than or equal to 100_F (37.78_C). S Fifteen second delay at termination of defrost before the auxiliary heat (W2) is de- energized. S Twenty second delay at termination of defrost before the outdoor fan is energized. S Seventy and sixty second compressor delays when Quiet Shift- 2 enabled.
PAGE 45
Fig. 33 – Control Board 1190261 (for units with ECM Fan Motor) The control board accumulates compressor run time. As the accumulated run time approaches the selected defrost interval time, the control board monitors the coil temperature sensor for a defrost demand. If a defrost demand exists, a defrost cycle will be initiated at the end of the selected time interval. A defrost demand exists when the coil temperature is at or below 32_F/0_C for 4 minutes during the interval.
PAGE 46
LIQUID LINE SOLENOID ACCESSORY In heat pump long line applications, a liquid line solenoid is required to control refrigerant migration in the heating mode. The solenoid should be installed near the outdoor unit with the arrow facing the outdoor unit. This is the direction of flow control. See Long Line Application Guideline for details.
PAGE 47
After a 15 minute delay, if there is still a call for cooling, the compressor contactor is energized. If the thermal protector has not re- set, the outdoor fan is turned off. If the call for cooling continues, the control will energize the compressor contactor every 15 minutes. If the thermal protector closes, (at the next 15 minute interval check), the unit will resume operation.
PAGE 48
Table 13— Status Codes Standby – no call for unit operation Standby – no call for unit operation Cooling Operation FAULT None On solid, no flash None Off None System Communications Failure High Pressure Switch Open Low Pressure Switch Open 1, pause Control Fault 45 Brown Out (24 v) 46 The control voltage is less than 15.5v for at least 4 seconds. Compressor and fan operation not allowed until control voltage is a minimum of 17.5v. Verify control voltage.
PAGE 49
Fig.
PAGE 50
Fig. 36 – Observer Communicating Wall Control Four- Wire Connection Wiring Diagrams (See Thermostat Installation Instructions for specific unit combinations) Variable Speed Furnace/Fan Coil Wall Control Green DX+ DX- S1 S2 Optional Remote Room Sensor White C Red R Yellow DX- White C Green DX+ Yellow Red R Humidifier Connection Outdoor DX+ DX- C R HUM LEGEND COM 24V FACTORY WIRING 24V FIELD WIRING FIELD SPLICE CONNECTION Fig.
PAGE 51
Fig. 38 – Non- Communicating Standard Thermostat 2- Wire 24V Circuit Connections A/C THERMOSTAT TPPICAL FURNACE OR FAN COIL AIR CONDITIONER 24VAC HOT R R R 24VAC COM C C C HEAT STAGE 1 W/W1 W HEAT STAGE 2 Y/Y2 Y INDOOR FAN G G Y FIEL INSTALLED JUMPER WIRE LEGEND 24V FACTORY WIRING 24V FIELD WIRING FIELD SPLICE CONNECTION NOTE: Wiring must conform to NEC or local codes. Fig.
PAGE 52
TWO- STAGE *CA7, *CA9, *CH6, *CH9 Table 14—Model Plug Information Application Guidelines ICP designed and tested the two- stage air conditioner and heat pump products with R- 410A refrigerant to operate at a minimum outdoor operating ambient in cooling mode at 55_F (12.8_C) and the maximum outdoor operating ambient in cooling is 125_F (51.6_C). The maximum outdoor operating ambient in heating mode is 66_F (18.8_C). Continuous operation in heating mode is approved to - 30_F (- 34.4_C).
PAGE 53
The control board accumulates compressor run time. As the accumulated run time approaches the selected defrost interval time, the control board monitors the coil temperature sensor for a defrost demand. If a defrost demand exists, a defrost cycle will be initiated at the end of the selected time interval. A defrost demand exists when the coil temperature is at or below 32_F for 4 minutes during the interval. The defrost cycle is terminated when the coil temperature reaches 65_F or 10 minutes has passed.
PAGE 54
CHECK CHARGE All Two- Stage units must be charged in high stage only. (See Charging Tables 8 & 10) Factory charge amount and desired subcooling are shown on unit rating plate. Charging method is shown on information plate inside unit. To properly check or adjust charge, conditions must be favorable for subcooling charging. Favorable conditions exist when the outdoor temperature is between 70_F and 100_F (21.11_C and 37.78_C), and the indoor temperature is between 70_F and 80_F (21.11_C and 26.67_C).
PAGE 55
67% capacity when the solenoid is not energized and 100% capacity when the solenoid is energized. The loading and unloading of the two step scroll is done “on the fly” without shutting off the motor between steps. NOTE: 67% compressor capacity translates to approximately 75% cooling or heating capacity at the indoor coil. The compressor will always start unloaded and stay unloaded for five seconds even when the thermostat is calling for high stage.
PAGE 56
S Check the high- voltage supply. The unit need not be running to check high voltage, but the power must be on. S If the 230vac is present, use Table 15 to check for proper control voltage output to the fan motor from the control board. The control board sends DC voltage signals to the motor through the terminals labeled PWM1 and PWM2 Set a voltmeter on a DC voltage scale and check across these terminals. S First check voltage with the motor disconnected.
PAGE 57
Control Box Contactor And Capacitor Removal of the control box cover exposes the control components. Both air conditioner and heat pump control boxes will appear to be nearly identical. There are two contactors, two capacitors, a control board and a compressor start assist. The contactors are identical to those used in the standard single speed units. One controls low capacity operation and the second controls high speed. The capacitors also are similar to those used in standard single speed units.
PAGE 58
TROUBLESHOOTING Troubleshooting circuit board FAST # 1185237, 1186140 The Communicating Series outdoor units all use the same control board. A model plug is used to identify the system type, and set the operating parameters for airflow, start circuit timing etc. (See Model Plug section.) Replacement boards may have a different part number from the original board. A newer board will always be backward compatible to previous units if it is superseded at Fast Parts.
PAGE 59
Troubleshooting units for proper switching between low & high stages - *CA7, *CA9, *CH6, *CH9 Check the suction pressures at the service valves. Suction pressure should be reduced by 3- 10% when switching from low to high capacity. NOTE: The liquid pressures are very similar between low and high stage operation, so liquid pressure should not be used for troubleshooting. Compressor current should increase 20- 45% when switching from low to high stage.
PAGE 60
Table 16—Two- Stage Compressor Resistances (Winding Resistance at 70_F±20_) Winding 024 036 048 060 Start (S- C) 1.64 1.52 1.86 1.63 Run (R- C) 1.30 0.88 0.52 0.39 Status Codes Table 17 shows the status codes flashed by the amber status light. Most system problems can be diagnosed by reading the status code as flashed by the amber status light on the control board. The codes are flashed by a series of short and long flashes of the status light.
PAGE 61
CARE AND MAINTENANCE Cleaning Coil To assure high performance and minimize possible equipment malfunction, it is essential that maintenance be performed periodically on this equipment. The frequency with which maintenance is performed is dependent on such factors as hours of operation, geographic location, and local environmental conditions. ! ! UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage or improper operation.
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Final Check- Out After the unit has been operating, the following items should be checked. 1. Check that unit operational noise is not excessive due to vibration of component, tubing, panels, etc. If present, isolate problem and correct. 2. Check to be sure caps are installed on service valves and are tight. . R- 410A REFRIGERANT QUICK REFERENCE GUIDE S S Observe all warnings, cautions, and bold text. S S S R- 410A refrigerant cylinders are rose colored.
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AIR CONDITIONER TROUBLESHOOTING CHART NO COOLING OR INSUFFICIENT COOLING COMPRESSOR WILL NOT RUN COMPRESSOR RUNS BUT CYCLES ON INTERNAL OVERLOAD COMPRESSOR RUNS BUT INSUFFICIENT COOLING CONTACTOR OPEN CONTACTOR CLOSED OUTDOOR FAN STOPPED OR CYCLING ON OVERLOAD LOOSE LEAD AT FAN MOTOR LOW SUCTION PRESSURE HIGH SUCTION LOW HEAD PRESSURE HIGH SUCTION LOW SUPERHEAT POWER SUPPLY COMPRESSOR POWER SUPPLY OPEN OUTDOOR AIR RESTRICTED OR RECIRCULATING MOTOR DEFECTIVE DIRTY AIR FILTERS DEFECTIVE COMPRE
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HEAT PUMP TROUBLESHOOTING HEATING CYCLE NO HEATING OR INSUFFICIENT HEATING COMPRESSOR WILL NOT RUN COMPRESSOR RUNS BUT CYCLES ON INTERNAL OVERLOAD COMPRESSOR RUNS INSUFFICIENT HEATING CONTACT OPEN CONTACTOR CLOSED DIRTY FILTERS OR INDOOR COIL DEFECTIVE LOWVOLTAGE TRANSFORMER COMPRESSOR POWER SUPPLY INDOOR FAN STOPPED OR CYCLING ON OVERLOAD DEFECTIVE FAN MOTOR CAPACITOR OUTDOOR FAN STOPPED OUTDOOR FAN RUNNING OUTDOOR THERMOSTAT DEFECTIVE REMOTE CONTROL CENTER DEFECTIVE LOOSE LEADS AT COMPRESSO
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HEAT PUMP TROUBLESHOOTING COOLING CYCLE NO COOLING OR INSUFFICIENT COOLING COMPRESSOR WILL NOT RUN COMPRESSOR RUNS BUT CYCLES ON INTERNAL OVERLOAD COMPRESSOR RUNS BUT INSUFFICIENT COOLING CONTACTOR OPEN CONTACTOR CLOSED OUTDOOR FAN STOPPED OR CYCLING ON OVERLOAD LOOSE LEAD AT FAN MOTOR LOW SUCTION PRESSURE HIGH SUCTION LOW HEAD PRESSURE HIGH SUCTION LOW SUPERHEAT POWER SUPPLY COMPRESSOR POWER SUPPLY OPEN OUTDOOR AIR RESTRICTED OR RECIRCULATING DEFROST RELAY N.C.
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INDEX OF TABLES DESCRIPTION PAGE # Table 1—Air Conditioner and Heat Pump Model Number Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Table 1—Air Conditioner and Heat Pump Model Number Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Table 2—Defrost Control Speed- Up Timing Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .