Residential Air Conditioners and Heat Pumps Using R---22 and Puronr Refrigerant Application Guideline and Service Manual TABLE OF CONTENTS PAGE PAGE UNIT IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 REFRIGERATION SYSTEM REPAIR . . . . . . . . . . . . . . . 32--34 SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 3 Leak Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 INTRODUCTION . . . . . . . . . . . . . . . . . . .
UNIT IDENTIFICATION This section explains how to obtain the model and serial number from unit rating plate. These numbers are needed to service and repair the Puronr 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.
SAFETY CONSIDERATIONS INSTALLATION GUIDELINE 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.
ACCESSORIES Table 1—Required Field--Installed Accessories for Air Conditioners ACCESSORY REQUIRED FOR LOW --- AMBIENT COOLING APPLICATIONS (Below 55°F/12.8_C) REQUIRED FOR LONG LINE APPLICATIONS* REQUIRED FOR SEA COAST APPLICATIONS (Within 2 miles/3.
ACCESSORY DESCRIPTIONS Refer to Table 1 for an Accessory Usage Guide for Air Conditioners and Table 2 for Heat Pumps. Refer to the appropriate section below for a description of each accessory and its use. 1. Crankcase Heater An electric resistance heater which mounts to the base of the compressor to keep the lubricant warm during off cycles. Improves compressor lubrication on restart and minimizes the chance of liquid slugging. Usage Guideline: Required in low ambient cooling applications.
LOW--AMBIENT COOLING GUIDELINE The minimum operating temperature for these units in cooling mode is 55_F/12.7_C outdoor ambient without additional accessories. This equipment may be operated in cooling mode at ambient temperatures below 55_F/12.7_C when the accessories listed in Table 1 or 2 are installed. Wind baffles are required when operating in cooling mode at ambients below 55_F/12.7_C. Refer to Fig. 1 for wind baffle construction details for Base through Comfort Series models and Fig.
LONG LINE GUIDELINE CABINET ASSEMBLY Refer to Residential Piping and Long Line Guideline for air conditioner and heat pump systems using Puron refrigerant or Long Line Guideline for R--22 Air Conditioners and Heat Pumps. Basic Cabinet Designs Certain maintenance routines and repairs require removal of the cabinet panels. There are 3 basic cabinet designs for air conditioning and heat pumps. Each design tier has options of standard or dense grills. (See Fig. 2).
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, louvers or coils to be damaged. It is recommended to protect the top cover from damage of tools, belt buckles, etc. while servicing from the top. 1. Should the unit height allow components to be accessed from the top of the unit, follow procedures for removing fan motor assembly. Access components through the top cap. 2.
Base and Comfort Series AC Control Box Base and Comfort HP Control Box Fig.
Labeling Wiring Label Charging Label Rating Plate Caution Label (3-phase only) Piston Label Warning Label Mid ---Tier / Deluxe Wiring Label Rating Plate Charging Label Caution Label Piston Label Warning Label Entry Fig.
ELECTRICAL ! 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. Contactor should pull in if voltage is correct and coil is good. If contactor does not pull in, replace contactor. 4. With high--voltage power off and contacts pulled in, check for continuity across contacts with ohmmeter.
Use following formula to calculate capacitance: Capacitance (mfd)= (2650 X amps)/volts 3. Remove any capacitor that shows signs of bulging, dents, or leaking. Do not apply power to a defective capacitor as it may explode. Sometimes under adverse conditions, a standard run capacitor in a system is inadequate to start compressor. In these instances, a start assist device is used to provide an extra starting boost to compressor motor.
Pressure Switches Pressure switches are protective devices wired into control circuit (low voltage). They shut off compressor if abnormally high or low pressures are present in the refrigeration circuit. Puron pressure switches are specifically designed to operate with Puronr systems. R--22 pressure switches must not be used as replacements for the Puronr air conditioner or heat pump. Puronr pressure switches are identified by a pink stripe down each wire.
Defrost Thermostat Defrost thermostat signals heat pump that conditions are right for defrost or that conditions have changed to terminate defrost. It is a thermally actuated switch clamped to outdoor coil to sense its temperature. Normal temperature range is closed at 30_ ± 3_F and open at 65_ ± 5_F. Defrost thermostats are used in Base and Comfort models, a coil temperature thermistor is used in Preferred and Infinity series units. FEEDER TUBE STUB TUBE DEFROST THERMOSTAT logic.
Troubleshooting (HK32EA001) 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. If 24 volts is present on the Y spade terminal, and the contactor is not closed, check voltage on contactor coil. If no voltage is present, check for opened pressure switch. 3.
14. Remove jumper between DFT and R terminals. Reconnect defrost thermostat leads. Failure to remove jumper causes unit to switch to defrost every 30, 60, or 90 minutes and remain in defrost for full 10 minutes. 15. Replace control box cover. Restore power to unit. If defrost thermostat does not check out following above items or incorrect calibration is suspected, check for defective thermostat as follows: 1. Follow items 1--5 above. 2.
If the defrost thermostat is closed, a complete defrost cycle is initiated. If the Quiet Shift switch is turned on, the compressor will be turned off for two 30 second intervals as explained previously. Troubleshooting (HK32EA003) If outdoor unit will not run: 1. Does the Y input have 24 volts from thermostat? If not, check thermostat or wire. If yes proceed to #2 2. The Y spade terminal should have 24 volts if Y input is energized.
COPELAND SCROLL COMPRESSOR 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. Scroll Gas Flow Compression in the scroll is created by the interaction of an orbiting spiral and a stationary spiral.
If replacement is deemed necessary, perform the following to replace sensor: 2. Carefully remove sensor cover 1. Locate top cap and discharge temperature sensor A12343 A12342 3. Expose the sensor holder 4.
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.
9. If a compressor hums but won’t start it could indicate either a voltage or amperage issue. Verify adequate voltage and operational start components if installed. If it is drawing excessive amperage and voltage doesn’t appear to be the problem it may be assumed a locked condition. Ensure refrigerant has had ample time to equalize and boil out of the compressor before condemning. 10.
Electrical Failures The compressor mechanical pump is driven by an electric motor within its hermetic shell. In electrical failures, compressor does not run although external electrical and mechanical systems appear normal. Compressor must be checked electrically for abnormalities. Before troubleshooting compressor motor, review this description of compressor motor terminal identification. Single--Phase Motors To identify terminals C, S, and R: 1. Turn off all unit power. 2.
REFRIGERATION SYSTEM Refrigerant ! WARNING UNIT OPERATION AND SAFETY HAZARD Failure to follow this warning could result in personal injury or equipment damage. Puronr refrigerant which has higher pressures than R--22 and other refrigerants. No other refrigerant may be used in this system. Gauge set, hoses, and recovery system must be designed to handle Puronr. If you are unsure consult the equipment manufacturer. ! Brazing This section on brazing is not intended to teach a technician how to braze.
Before brazing the line set to the valves, the belled ends of the sweat connections on the service valves must be cleaned so that no brass plating remains on either the inside or outside of the bell joint. To prevent damage to the valve and/or cap “O” ring, use a wet cloth or other acceptable heat--sinking material on the valve before brazing. To prevent damage to the unit, use a metal barrier between brazing area and unit.
Heating Piston (AccuRaterr) -- Heat Pumps Only In this product line, AccuRater pistons are used to meter refrigerant for heat pump heating mode only. All indoor coils are supplied with a bi--flow TXV for metering in the cooling mode. AccuRaterr piston has a refrigerant metering hole through it. The piston seats against the meters refrigerant in to the outdoor coil in heating and allows refrigerant to flow around it in cooling mode. There are 2 types of liquid line connections used.
Reversing Valve In heat pumps, changeover between heating and cooling modes is accomplished with a valve that reverses flow of refrigerant in system. This reversing valve device is easy to troubleshoot and replace. The reversing valve solenoid can be checked with power off with an ohmmeter. Check for continuity and shorting to ground. With control circuit (24v) power on, check for correct voltage at solenoid coil. Check for overheated solenoid.
Liquid Line Filter Drier Install Liquid--line Filter Drier Indoor -- HP Filter driers are specifically designed for R--22 or Puronr refrigerant. Only operate with the appropriate drier using factory authorized components. It is recommended that the liquid line drier be installed at the indoor unit. Placing the drier near the TXV allows additional protection to the TXV as the liquid line drier also acts as a strainer. Refer to Fig.
Accumulator The accumulator is specifically designed to operate with Puronr or R22 respectfully; use only factory--authorized components. Under some light load conditions on indoor coils, liquid refrigerant is present in suction gas returning to compressor. The accumulator stores liquid and allows it to boil off into a vapor so it can be safely returned to compressor.
Thermostatic Expansion Valve (TXV) All fan coils and furnace coils will have a factory installed thermostatic expansion valve (TXV). The TXV will be a bi--flow, hard--shutoff with an external equalizer and a balance port pin. A hard shut--off TXV does not have a bleed port. Therefore, minimal equalization takes place after shutdown. TXVs are specifically designed to operate with Puronr or R--22 refrigerant, use only factory authorized TXV’s. Do not interchange Puron and R--22 TXVs.
Replacing TXV on an Indoor Coil (pre--2006) 1. Pump system down to 2 psig and recover refrigerant. 2. Remove coil access panel and fitting panel from front of cabinet. 3. Remove TXV support clamp using a 5/16--in. nut driver. Save the clamp. 4. Remove R--22 TXV using a backup wrench on flare connections to prevent damage to tubing. 5. Using wire cutters, cut equalizer tube off flush with vapor tube inside cabinet. 6. Remove bulb from vapor tube inside cabinet. 7. Braze equalizer stub--tube closed.
REFRIGERATION SYSTEM REPAIR Leak Detection New installations should be checked for leaks prior to complete charging. If a system has lost all or most of its charge, system must be pressurized again to approximately 150 psi minimum and 375 psi maximum. This can be done by adding refrigerant using normal charging procedures or by pressurizing system with nitrogen (less expensive than refrigerant). Nitrogen also leaks faster than refrigerants.
Compressor Removal and Replacement System Clean--Up After Burnout Once it is determined that compressor has failed and the reason established, compressor must be replaced. Some compressor electrical failures can cause motor to burn. When this occurs, by--products of burn, which include sludge, carbon, and acids, contaminate system. Test the oil for acidity using POE oil acid test to determine burnout severity. If burnout is severe enough, system must be cleaned before replacement compressor is installed.
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.
TROUBLESHOOTING WITH SUPERHEAT This troubleshooting routine was developed to diagnose cooling problems using superheat in TXV systems. It is effective on heat pumps in cooling mode as well as air conditioners. The system must utilize a TXV as the expansion device in cooling mode. Basic Diagnostics NOTE: When checking refrigerant charge and troubleshooting operating systems, the indoor airflow has significant effect on the determination.
High Superheat with Normal or High Suction Pressure NOTE: Normal to High suction pressure is considered for R--22: > ∼65 psig, Puron: > ∼110 psig. An application issue or other system component failure typically causes this condition. 15. Check airflow, sensing bulb tightness, orientation on vapor tube and ensure bulb is properly wrapped. S If OK proceed to Step 16 16.
Table 5—Puron System Suction Pressure Drop Nominal Size (Btuh) 18000 18000 18000 24000 24000 24000 30000 30000 30000 36000 36000 36000 42000 42000 42000 42000 48000 48000 48000 60000 60000 60000 Suction Line OD (in.) Pressure Drop (psi/100 ft) Suction Velocity fpm 1/2 9.9 1649 5/8 3.1 1018 3/4 1.2 678 1/2 16.7 2199 5/8 5.2 1357 3/4 2.0 904 7/8 1.0 678 5/8 7.8 1696 3/4 2.9 1130 7/8 1.5 848 5/8 10.9 2036 3/4 4.1 1356 7/8 2.0 1017 5/8 14.1 2375 3/4 5.4 1582 7/8 2.7 1187 1 1/8 0.8 696 3/4 6.9 1808 7/8 3.
Table 6—R--22 System Suction Pressure Drop Nominal Size (Btuh) 18000 18000 18000 18000 24000 24000 24000 30000 30000 30000 36000 36000 36000 42000 42000 42000 48000 48000 48000 60000 60000 60000 Line OD (in.) Pressure Drop (psi/100 ft) Suction Velocity Fpm 5/8 13.6 5/8 4.0 3/4 1.5 7/8 0.8 5/8 6.7 3/4 2.5 7/8 1.3 5/8 10.1 3/4 3.8 7/8 1.9 3/4 5.3 7/8 2.6 1 1/8 0.7 3/4 7.0 7/8 3.5 1 1/8 1.0 3/4 8.9 7/8 4.4 1 1/8 1.2 7/8 6.7 1 1/8 1.8 1 3/8 0.
Table 7—Puronr Refrigerant Pressure Temperature Chart PSIG 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 19.8 20.9 22.0 23.2 24.3 25.3 26.4 27.4 28.5 29.5 30.5 31.5 32.5 33.4 34.4 35.3 36.
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.
Table 9—Puron 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
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 27 28 29 30 31 33 34 35 36 37 38 39 39 40 41 42 43 44 45 46 47
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
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
TWO--STAGE 25HNB/24ANB Application Guidelines Model Plug Carrier designed and tested the two--stage air conditioner and heat pump products with Puron refrigerant to operate at a minimum outdoor operating ambient in cooling mode at 55_F without low ambient cooling enabled and the maximum outdoor operating ambient in cooling is 125_F/51.6_C. On Infinity communicating systems, only low ambient cooling is available to 0_F/--17.8_C. The maximum outdoor operating ambient in heating mode is 66_F/18.
Airflow Selections for 24ANB7 / 25HNB6 / 24ANB1 /25HNB9 Using Non--Communicating (Non--Infinity) Thermostats Airflow Selection for 58CVA/58MVB Furnaces The 58CVA/58MVB variable--speed furnaces provide high--and low--stage blower operation to match the capacities of the compressor at high and low stages. To select the recommended airflow and for adjustments to the manual switches labeled SW1--5, AC, and CF on the control board, refer to the furnace Installation Instructions.
S The ODF fan delay defeat can be toggled by shorting the forced defrost pins for >15 seconds while in the standby mode (status LED on solid). The LED will start to flash when the toggle has taken place. S Status code 4 shows the fan delay defeat is active (no delay) Status code 3 shows that it is not active (20 second delay) The code will continue to be displayed until after the short is removed. Once the short is removed, there is a 5 second wait before the code is cancelled.
refrigerant charge may not be correct. Do not use chart to adjust refrigerant charge. NOTE: In heating mode, check refrigerant charge only when pressures are stable. If in doubt, remove charge and weigh in correct refrigerant charge. NOTE: When charging is necessary during heating season, charge must be weighed in accordance with unit rating plate, ±0.6 oz./ft. of 3/8--in. liquid--line above or below 15 ft., respectively. EXAMPLE: To calculate additional charge required for a 25--ft. line set: 25 ft.
The outdoor Integral Control Motor (ECM), is a variable--speed motor which operates from 450 to 850 rpm. The motor is a dc permanent magnet--type motor with the electronic controls integrated into its rear cover. The control package includes a small diode bridge, capacitors, and power switching devices. It converts ac to dc power and switches the dc power to the motor windings on and off at various rates to control the motor speed.
Muffler, Accumulator, Reversing Valve (RVS) Control Box The Puronr two--stage air conditioners and heat pumps have a compressor discharge line muffler, to dampen sound pressure pulsations. The Puronr two--stage heat pumps have a specifically designed reversing valve, for Puronr application and an accumulator for storing excess liquid refrigerant during the heating mode to prevent damaging flood--back. Contactor And Capacitor Removal of the information plate exposes the control components.
A B C A B C A B C A B C UTILITY RELAY * UTILITY SIGNAL OPEN RELAY LLS Liquid Line Solenoid * SUPPLIED BY UTILITY PROVIDER A12260 A12261 Fig. 33 – 2--Stage Control Board TROUBLESHOOTING Troubleshooting circuit board HK38EA016, 022, 023 The Infinity 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.
230v Brown--Out Protection Defeated The brownout feature can be defeated if needed for severe noisy power conditions. This defeat should always be a last resort to solving the problem. Defeat is available on the User Interface setup screen (available with SYSTXBBUID01--C UI) or can be initiated through the forced defrost pins for non--communicating systems as follows: The brownout toggle is accomplished by shorting the defrost pins from power up with the OAT and OCT sensor connector removed.
Temperature Thermistors Thermistors are electronic devices which sense temperature. As the temperature increases, the resistance decreases. Thermistors are used to sense outdoor air (OAT) and coil temperature (OCT). Refer to Fig. 31 for resistance values versus temperature. If the outdoor air or coil thermistor should fail, the control will flash the appropriate fault code. (See Table 16) IMPORTANT: The outdoor air thermistor and coil thermistor should be factory mounted in the final locations.
Table 15—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 16 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.
Thermidistat Fan Coil Heat Pump O Thermidistat Furnace Heat Pump O O RVS Cooling W1 O/B W2 W2 RVS Cooling O/B W2 W1 Heat Stage 3 W/W1 W2 Heat Stage 3 (furnace) W/W1 W/W1 Heat/Cool Stage 1 Y1 / W2 Y1 Y1 Heat/Cool Stage 1 Y1 / W2 Y1 Y1 Heat/Cool Stage 2 Y/Y2 Y/Y2 Y2 Heat/Cool Stage 2 Y/Y2 Y/Y2 Y2 J2 Jumper on Control Board Fan G G Fan G G 24VAC Hot Heating Rh R 24VAC Hot Heating Rh R 24VAC Hot Cooling Rc 24VAC Hot Cooling Rc Dry Contact 1 D1 Dry Contact 1
TWO STAGE NON--COMMUNICATING 24ACB7/25HCB6 These units are a low cost 2--stage option that is non--communicating utilizing 2 stage scroll technology. These units require Performance Boost furnace (58PH, 58MEB), variable speed furnace (58MV, 58CV) or new model variable speed fan coil (FV4C). Variable speed fan coils prior to the FV4C will NOT be rated with the new Comfort series two stage units as they are not capable of meeting the air flow requirements necessary for rating.
SYSTEM FUNCTION AND SEQUENCE OF OPERATION (24ACB7/25HCB6) NOTE: Defrost control board is equipped with 5 minute lockout timer that is initiated upon any interruption of power. Turn on power to indoor and outdoor units. Transformer is energized. These models utilize a 2--stage indoor thermostat. With a call for first (low) stage cooling or heating, the outdoor fan and low--stage compressor are energized.
To check system operation during heating cycle, refer to the Heating Check Chart on outdoor unit. This chart indicates whether a correct relationship exists between system operating pressure and air temperature entering indoor and outdoor units. If pressure and temperature do not match on chart, system refrigerant charge may not be correct. Do not use chart to adjust refrigerant charge.
CARE AND MAINTENANCE 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. ! WARNING ELECTRICAL SHOCK HAZARD Cleaning Coil 1. Remove top cover. (See Remove Top Cover in Cabinet section of this manual.) 2.
Electrical Controls and Wiring 1. Disconnect power to both outdoor and indoor units. 2. Check all electrical connections for tightness. Tighten all screws on electrical connections. If any connections appear to be burned or smoky, disassemble the connection, clean all parts and stripped wires, and reassemble. Use a new connector if old one is burned or corroded, and crimp tightly. 3. Reconnect electrical power to indoor and outdoor units and observe unit through 1 complete operating cycle. 4.
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
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 COMPRESS
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.
INDEX OF TABLES DESCRIPTION TABLE # Required Field--Installed Accessories for Air Conditioners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Required Field--Installed Accessories for Heat Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Defrost Control Speed--Up Timing Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Copyright 2012 Carrier Corp. S 7310 W. Morris St. S Indianapolis, IN 46231 Edition Date: 07/12 Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations. 64 Catalog No.
