Page 1 Service Data Book Sold By American Refrigeration Supplies Inc. Wholesale Distribution North America...
Page 2: Table Of Contents
A LOOK AT SERVICE SAFETY GENERAL SERVICE SAFETY PRECAUTIONS Introduction ......2 Trained Personnel Only ....2 III.
Page 3: Introduction
ﬂames that can In the interest of promoting safety in the refrigera- lead to serious burns or death. When spray from ter- tion and air conditioning industry, Tecumseh Prod- minal venting is ignited this is called “terminal vent- ucts...
Page 4 A LOOK AT SERVICE SAFETY Figure 1-1. Compressor with (1) protective Figure 1-4. Compressor with (1) protective terminal cover and (2) bale strap terminal cover held in place by (2) removed to show (3) hermetic metal bale strap. terminal. Figure 1-2. Close-up view of hermetic terminal showing individual Figure 1-5.
Page 5: Refrigerants And Other Chemicals
Refrigerants and Other To avoid serious injury or death, be sure to remove and recover all refrigerant before Chemicals removing the compressor. Contact with refrigerant, mixtures of refrigerant and oil, or other chemicals can cause a variety of injuries Use a tubing cutter, not a torch. including burns and frostbite.
Page 6: System Charging
A LOOK AT SERVICE SAFETY Use a pressure regulating valve and pressure Do not pressurize the system beyond 150 gauges. PSIG ﬁeld leak test pressure. When ﬁeld testing a system for leaks, 150 Commercial cylinders of nitrogen contain PSIG is adequate test pressure. pressures in excess of 2000 PSIG at 70°F.
Page 7: Prevention Of Water-Utilizing System
the original equipment manufacturer’s service B. How an Explosion Occurs information. If the refrigerant tubing in the heat exchanger devel- ops a leak, water can enter the refrigerant side of the Overcharging the system immerses the com- system. Water entering the refrigerant side can come pressor motor, piston, connecting rods, and in contact with live electrical connections in the cylinders in liquid refrigerant.
Page 8: Start Capacitor Overheating
Follow the Labels Tecumseh Products Company compressors have • a high-pressure cut-out which interrupts power labels and markings with important information. to ALL leads to the compressor, or For your safety and the safety of others, read the •...
Page 9 A LOOK AT SERVICE SAFETY MODEL AND APPLICATION INFORMATION Compressor Model Number Codes ..10 Condensing Unit Model Number Codes . . 11 III. Serial Label Information ....12 Basic Application Information for Hermetic Compressors .
Page 10: Compressor Model Number Codes
Release Number of First T wo Compressor Condensing Variant Application Digits In Rated Digits of Rated Refrigerant Voltage Family Units (Generation) BTU Capacity BTU Capacity In this example (4) total digits, with See unit information on next page. the first two (40), or 4,000 BTU capacity . Primary Voltage Codes Primary Application Parameters...
Page 11: Condensing Unit Model Number Codes
AEA4440YXA XC 1. E=Evaporative Condensate Units. X=A holding character, reserved for future use. 2. Condensing Unit Features, see chart below. Unassigned Letters: R The letters I, O and Q are eliminated A Standard Unit B Std. Unit w/Receiver Tank C Std. Unit w/Tank & BX Cable D Std.
Page 12: Serial Label Information
III. Serial Label Information compressors, the serial label is afﬁxed in the same The only source for complete compressor informa- location. Both describe the characteristics of the tion is on the compressor serial label. On earlier compressor. compressors, the serial plate is usually spotwelded on the upper housing of the compressor.
Page 13 A LOOK AT SERVICE SAFETY Manufacturing Code Date COMPRESSORS THERMALLY VOLTAGE EVAP. PROTECTED RANGE (ºF) Month = September R.L.A. E.A. 60 HZ 50 HZ L.R.A. E.A. -10F TO +45F 58.8 FANS: DESIGN PRESSURE P.S.I. MIN. CIRCUIT F.L.A. E.A. PROTECTED HI SIDE LO SIDE AMPACITY THERMALLY...
Page 14: Hermetic Compressors
Basic Application Information Tecumseh hermetic compressors are designed for one of the following evaporator temperature ranges for Hermetic Compressors shown in Table 2-2. Tecumseh hermetic compressors are engineered to do speciﬁc air conditioning and refrigeration tasks. B. Refrigerant Hermetic compressors are designed for a particular evaporator temperature range and a speciﬁc refriger-...
Page 15 A LOOK AT SERVICE SAFETY COMPRESSOR MOTOR AND COMPONENT INFORMATION Single Phase Compressor Motor Types . 16 PSC Motor Starting ....18 III. Hermetic Compressor Thermal Protectors .
Page 16: Single Phase Compressor Motor Types
Single Phase Compressor Alt. 3/4" Thermal Protector Motor Types Tecumseh hermetic compressors contain motors 4 T M Thermal Protector designed for speciﬁc requirements of starting torque Control Line 1 and running efﬁciency. There are four general types Line 2 of single phase motors, each distinctly different from Identified Conductor the others.
Page 17 A LOOK AT SERVICE SAFETY C. Capacitor Start and Run (CSR) This motor may use either: This motor arrangement uses a start capacitor and a • an external thermal protector, or run capacitor in parallel with each other and in •...
Page 18: Psc Motor Starting
PSC Motor Starting Minimum starting voltage for the compressor when it is attempting to start (locked rotor) is: Tecumseh Products Company has pioneered in encouraging the development of Permanent Split Table 3-7: Minimum Starting Voltage Capacitor compressor motors. This type of motor...
Page 19: Hermetic Compressor Thermal Protectors
A LOOK AT SERVICE SAFETY III. Hermetic Compressor Thermal Protectors Hermetic compressor motors are protected from overheating by thermal protectors built into or mounted in contact with the compressor motor. See the Electrical Service Parts Guide Book for correct replacement thermal protectors. Typical wiring dia- grams are shown on pages 51 to 82.
Page 20 Table 3-2: Facts About Thermal Protectors • Currently used on all AE, AK, AZ, RK, and AJ models • Sense motor current and housing temperature or combination thereof • Break line current when tripped • Generally do not protect against loss of charge External Line-Break Thermal •...
Page 21 A LOOK AT SERVICE SAFETY • Terminals M and M are a normally closed B. “AN” Wiring on Typical 230/200 Volt System with Electronic Protection switch actuated by the motor sensor circuit. Module Switch contacts are rated at 2.5 amps at 265 volts maximum.
Page 22 24 Volt Compressor Line Voltage Compressor 2 Speed Motor Sensors C'Case Heaters Power Connections Table 3-3: "AN" Wiring on Typical System Min. Capacity Cond. Model RLA LRA BTU/HR Size AN5590E/F 92,500 #8 TW AN5610E/F 100,000 #8 TW Use Copper Conductors Only AN5612E/F 122,000 #6 TW...
Page 23 24 Volt Compressor Line Voltage Compressor 2 Speed Motor Sensors C'Case Heaters Power Connections Table 3-4: "AN" Wiring on Typical 460 Volt System Min. Min. Capacity Model Cond. Cont.* BTU/HR Size Size AN5590E/F 92,500 #12 TW 20 A AN5610E/F 100,000 14.5 #12 TW 20 A...
Page 24 24 Volt Not Used On Compressor Line Voltage Compressor 2 Speed Motor Sensors Internal Line Break C'Case Heaters Power Connections Models (G & H Suffix) Use Copper Conductors Only See Table 3-5 Table 3-5: "AN" Wiring on Typical System with Thermal Protector # 14 Min.
Page 25 Ground Black Tie Clear Tie Compressor Terminal Fence Contactor Crankcase Heaters To Control Circuit 3 Ph. Incoming Power Figure 3-15. Small terminal block wiring on typical system with thermal protector.
Page 26 Table 3-6: Small Terminal Block Information Line Texas Circuit Control Circuit Tecumseh Instruments T1, T2, M1, M2, Part Parts V.A.C., 1-PH V.A.C., Number Number 1-PH Ground 15AA1104A 90613 24 or 115 or 230 V.A.C. 24 V.A.C. 15AA1104B 90613-2 24 or 115 or 230 V.A.C.
Page 27: Compressor Motor Starting Relays
Upon startup, as current starts to ﬂow to the start power or other generalized rating. Select the correct winding, the resistance rapidly rises to a very high relay from the Tecumseh Electrical Service Parts value thus reducing the start winding current to a Guide Book.
Page 28 relay coil energized and the relay starting contacts open. When power is shut off to the motor, the volt- age drops to zero, the coil is de-energized, and the start contacts reset. When changing a compressor relay, care should be taken to install the replacement in the same position as the original.
Page 29 Potential Type Relay Supplier Code Designations tion, an explanation of the code numbers should be useful in the ﬁeld. In recent years, Tecumseh has used an increasing number of potential relays with hermetic compres- Tecumseh has two major suppliers of potential sors.
Page 30 16 = "L" Bracket for "FB" model compressors Note: Room temperature calibratio 20 = "L" Bracket for Tecumseh Twins = 1 1/2 HP and larger n is 5 to 7% lower than these values. 21 = "L" Bracket for capacitor box mounting 29 = Flat Bracket (Marion) was "14"...
Page 31 A LOOK AT SERVICE SAFETY NOTE: As noted above, the 4th digit in the code tion.Mounting in any other position can change the number of G.E. relays and the 7th digit for White relay’s operating characteristics enough so that the Rodgers relays indicates the position in which the compressor will not start properly.
Page 32: Selecting Capacitors
To eliminate this, Tecumseh Products Company In some instances, for reasons of both space and eco- start capacitors are equipped with bleeder resistors nomics, it is advantageous to use two capacitors wired across the capacitor terminals.
Page 33 A LOOK AT SERVICE SAFETY Table 3-7: Facts About Capacitors Compressor Capacitor Type Characteristics Motor Type • Designed to operate for only a few seconds during start • Taken out of start winding circuit by relay • Excessive start capacitor MFD increases start winding current, increases start winding temperature, and may reduce start torque •...
Page 34: Identification Of Terminal Pins
While the protective ter- minal cover may identify the terminal pins, it is pri- Tecumseh terminal pins are now always thought of marily designed to reduce the risk of serious injury in the order: Common, Start, Run. To identify the...
Page 35 A LOOK AT SERVICE SAFETY Common Start Common Start 1 Phase 1 Phase 3 Phase 3 Phase 1 Phase 3 Phase Screw-On Type Terminal Pins Screw-On Type Terminal Pins AG, AN & SF Models CL Models 24 Volt Compressor Line Voltage Compressor 2 Speed Motor Sensors...
Page 36: Fuse And Circuit Breaker Sizing
VII. Fuse and Circuit Breaker fault of a unit utilizing a hermetic compressor shall be no more than the sum of 225% of the compressor Sizing Related Load Amps (RLA) as marked on the system The following information applies to Compressor serial label, plus the RLA values of each of the other Motor - Branch Circuit, Short Circuit and Ground motors which use the same branch circuit.
Page 37 A LOOK AT SERVICE SAFETY SERVICING Introduction......38 Servicing or Troubleshooting Water-Utilizing Systems: Preventing Explosions .
Page 38 Introduction causes and solutions. This chapter also provides This chapter provides information to assist service greater detail about speciﬁc compressor problems. personnel in identifying and correcting compressor problems. It provides a general troubleshooting For your safety, read and follow the “General Service chart that relates complaints or problems to possible Safety Precautions”...
Page 39 A LOOK AT SERVICE SAFETY Servicing or Troubleshooting have at least one of these, DISCONNECT ALL ELECTRICAL POWER and look for indications Water-Utilizing Systems: that water has leaked into the refrigerant side of the Preventing Explosions system. These indications may include: In certain water-utilizing refrigeration systems, •...
Page 40 • a high-pressure cut-out which interrupts power If water does come out of the process valve, the entire system must be replaced. See “Replacing a to ALL leads to the compressor, or Single-Wall Water-Utilizing System” below. • an external pressure relief valve. If water does not come out of the process valve, Also, if you found a ground fault in the compressor there is still a possibility that some water has leaked...
Page 41 A LOOK AT SERVICE SAFETY III. Troubleshooting Chart For your safety, read and follow the “General Service • Prevention of Water-Utilizing System Explo- Safety Precautions” (on pages 2-7), as well as the ref- sions erenced troubleshooting procedures in this chart. •...
Page 42 Troubleshooting Chart- continued Complaint Possible Causes Response Compressor will not start—hums but trips on thermal protector 1. Improperly wired. Check against wiring diagram and wire properly. 2. Low voltage to compressor. Turn off system until proper voltage is restored. 3. System component, such as thermostat or control/contactor, not functioning Refer to the OEM service information.
Page 43 A LOOK AT SERVICE SAFETY Troubleshooting Chart- continued Complaint Possible Causes Response Compressor starts and runs, but short cycles on thermal protector 1. Too much current passing through thermal protector: a. Extra sources of current draw. a. Check wiring diagram. Check for extra sources of current passing through thermal protector (such as fan motors, pumps.) Refer to the...
Page 44 Troubleshooting Chart- continued Complaint Possible Causes Response Unit runs OK, but run cycle is shorter than normal (due to component(s) other than thermal protector) 1. System components, such as thermostat, control or contactor, not Refer to the OEM service information. functioning properly.
Page 45 A LOOK AT SERVICE SAFETY Troubleshooting Chart- continued Complaint Possible Causes Response Space or cabinet temperature too high 1. System problems, such as: a. control setting too high a. Refer to the OEM service information. b. expansion valve too small b.
Page 46 Troubleshooting Chart- continued Complaint Possible Causes Response In water-utilizing systems, reports or observations of any of the following: • system has made gurgling or percolating noises • water has leaked to outside of the system. • compressor giving off an unusual amount of heat.
Page 47 A LOOK AT SERVICE SAFETY Identifying Compressor • the compressor is properly connected to ground. Electrical Problems Never reset a breaker or replace a fuse without This section describes procedures for checking the ﬁrst checking for a ground fault. An open fuse compressor’s electrical circuits and components.
Page 48 Section B. Why use a megger or Hi-Pot? Tecumseh Products Company recom- mends checking for a ground fault only with a megger or Hi-Pot. A conventional ohmmeter will not reliably detect a ground fault under certain circum- stances.
Page 49 A LOOK AT SERVICE SAFETY Table 4-1: Checking for Proper Continuity and Resistance Single Phase Compressors 3-Phase Compressors Step 1: Allow When servicing single compressors with When servicing 3-phase compressors Thermal internal thermal protectors, be sure to with internal thermal protectors, be sure Protector allow time for the thermal protector to to allow time for the thermal protector to...
Page 50 C. Checking For Other Electrical Problems With that information, use Table 4-2 to determine the location of the procedure for the compressor you in Single Phase Motors are servicing. This section provides procedures for checking the components such as the thermal protector, relay and For more information on: capacitor in a single phase compressor.
Page 51 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. External Thermal Protector Control Relay — Current...
Page 52 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 53 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. (wired) Alt. 3/4" Thermal Protector 4 T M Thermal Protector...
Page 54 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 55 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. (module) Thermal Protector Control...
Page 56 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 57 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. External Thermal Protector Control Line 1...
Page 58 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 59 A LOOK AT SERVICE SAFETY • Prolonged operation on start cycle due to low voltage. Step 5: Check Start Capacitor- Continued Determine if the line voltage is too low (less than 90% of rated voltage). • Prolonged operation on start cycle due to incorrect relay.
Page 60 If replacement parts are needed, refer to the Tecum- Internal External Current Potential Start seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. External Thermal Protector Control Line 1...
Page 61 A LOOK AT SERVICE SAFETY Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48).
Page 62 Step 6: Check Start Capacitor CAUTION: Using a 20,000 ohm resistor, discharge the capacitor before removing it from the system to avoid damage to measuring devices and risk of electric shock. Disconnect the start capacitor from the system. Use a capacitance meter to measure the capacitance.
Page 63 If replacement parts are needed, refer to the Tecum- Internal External Current Potential Start seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. External Thermal Protector Control Line 1...
Page 64 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 65 A LOOK AT SERVICE SAFETY Step 3: Check Run Capacitor- b. Rx100,000 scale: If there is no needle deﬂection on an Continued analog meter or if a digital meter indicates inﬁnite resis- tance, then the run capacitor is open and needs to be replaced.
Page 66 • Excessive short cycling. Short cycling can be caused by Step 4: Check Start Capacitor- Continued problems with the compressor’s thermal protector or sys- tem components such as the thermostat, control, contac- tor, or high or low pressure cut-out. For more information on troubleshooting the thermal protector, see Step 3.
Page 67 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. Internal Thermal Protector Line 1 Line 2...
Page 68 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 69 A LOOK AT SERVICE SAFETY Before checking the relay, be sure it is mounted at the proper Step 4: Check Potential Relay position. (See pages 28-32.) Check the potential relay by mea- suring continuity between: a. Relay terminals 5 and 2. If there is no continuity, replace the relay.
Page 70 • Prolonged operation on start cycle due to low voltage. Step 5: Check Start Capacitor- Continued Determine if the line voltage is too low (less than 90% of rated voltage). • Prolonged operation on start cycle due to incorrect relay. Replace with correct relay. •...
Page 71 A LOOK AT SERVICE SAFETY This PSC Compressor Has the Following The electrical system on this type of motor is shown in Figure 4-10. The actual position of terminals on Components: the relay may be different than shown in Figure 4- 10.
Page 72 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 73 A LOOK AT SERVICE SAFETY Step 6: Add Start Assist Kit If the compressor checks out satisfactory on all the above PSC tests, but still doesn’t operate, add proper start assist kit to pro- vide additional starting torque. See Figure 4-11 for proper wir- ing.
Page 74 Protector If replacement parts are needed, refer to the Tecum- Type Type seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Internal External Current Potential Start Products Company at 1-800-211-3427. Internal Thermal Protector...
Page 75 A LOOK AT SERVICE SAFETY Step 1: Before Continuing with WARNING! All electric power should be disconnected and you Troubleshooting... should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48).
Page 76 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. (wired) Alt. 3/4" Thermal Protector 4TM Thermal Protector...
Page 77 A LOOK AT SERVICE SAFETY Step 1: Before Continuing with WARNING! All electric power should be disconnected and you Troubleshooting... should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48).
Page 78 Internal External Current Potential Start If replacement parts are needed, refer to the Tecum- seh Electrical Service Parts Guide Book for informa- tion on proper replacement parts, or call Tecumseh Products Company at 1-800-211-3427. (module) (plug-in) Thermal Protector...
Page 79 A LOOK AT SERVICE SAFETY Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48).
Page 80 Step 5: Check Module PTC Relay Check the relay by measuring continuity between the starting and protector package pin holes where the R and S pins on the compressor are inserted. If there is no continuity, the relay may be open. Wait 3 minutes, then check continuity again. If there is still no continuity, replace the protector package.
Page 81 Figure 4-16. If replacement parts are needed, refer Tecumseh Products Company at 1-800-211-3427. to the Tecumseh Electrical Service Parts Guide Book Sensor T erminals From Protection Module (S1, S2) Connector Block...
Page 82 Step 1: Before Continuing with WARNING! All electric power should be disconnected and Troubleshooting... you should have already made sure that the compressor does not have a ground fault (see “Checking for a Ground Fault” on pages 47-48). You should have also checked the windings for continuity and proper resistance (see “Checking for Conti- nuity and Proper Resistance”...
Page 83 200 psig pressure difference every in-warranty compressor that is returned to between suction and discharge. If compressor does them. The Tecumseh factory tears down and exam- not pump adequately, compressor must be replaced ines a representative sample of compressors returned with no further testing.
Page 84 Chapter 4...
Page 85 A LOOK AT SERVICE SAFETY INSTALLATION AND REPLACEMENT INFORMATION Compressor Tube Connections ..86 Refrigerant Line Sizes ....88 III. Refrigerant Line Pressure Drops ..93 Refrigerant Line Velocities .
Page 86: Compressor Tube Connections
Identiﬁcation of compressor connections can usually be accomplished without difﬁculty; however, occa- Connections sionally some question arises concerning oil cooler Tecumseh Products Company supplies compressors tubes and process tubes. to hundreds of manufacturers requiring different tubing sizes and arrangements. Because of this the Oil cooler tubes are found only in low temperature same compressor model may be found in the ﬁeld in...
Page 87 A LOOK AT SERVICE SAFETY Discharge Discharge Tube Tube Air Conditioning Discharge Tube Discharge Tube Discharge Discharge Tube Tube Figure 5-1. Standard discharge tubing arrangements - continued. Installation and Replacement Information...
Page 88: Refrigerant Line Sizes
Refrigerant Line Sizes return gas is “wet” at the compressor, a suction line accumulator should be installed adjacent to the compressor. A. R-12 and R-22 Refrigerant Line Sizes for • On systems with evaporators below -10°F, the Remote Systems Commercial oil/refrigerant mixture reaches a maximum vis- Refrigeration cosity when the refrigerant superheat is about...
Page 89 A LOOK AT SERVICE SAFETY Table 5-1: R-12 Refrigerant Line Sizes for Remote Systems Commercial Refrigeration SUCTION LINE SIZES Cond. Unit AT SYSTEM EVAPORATOR DESIGN TEMPERATURE CAPACITY Liquid Line (BTU/Hr.) -40°F -20°F 0°F +20°F +40°F Size 1200 2400 3600 4800 1 1/8 6000 1 1/8...
Page 90 B. R-22 Refrigerant Line Sizes for Remote Consider these installation notes: Systems Air Conditioning and Heat • Suction line sizes (up ﬂow) provide adequate Pumps gas velocities to assure oil return to the com- Condensers and evaporators should be designed and pressor and, therefore, remain constant in size circuited to maintain adequate velocity to prevent regardless of the vertical lift.
Page 91 A LOOK AT SERVICE SAFETY for up ﬂow. C. R-502 and R-134a Refrigerant Line Sizes for Remote Systems Commercial • Assurance of satisfactory sound level. (The Refrigeration tube size should be limited to maintain veloci- The selection of suction gas line sizes should be ties no greater than 3000 fpm.) guided by the following criteria: •...
Page 92 Table 5-5: R-134a Refrigerant Line Sizes for Remote Systems Commercial Refrigeration SUCTION LINE SIZES Cond. Unit AT SYSTEMS EVAPORATOR DESIGN TEMPERATURE CAPACITY Liquid Line (BTU/Hr.) -40°F -20°F 0°F +20°F +40°F Size 1200 2400 3600 4800 1 1/8 6000 1 1/8 7200 1 3/8 1 1/8...
Page 93: Refrigerant Line Pressure Drops
A LOOK AT SERVICE SAFETY III. Refrigerant Line Pressure Drops Tons of Refrigeration BTU's Per HR NOTE: Pressure drops do not allow for pulsating flow. If flow is pulsating, use next larger pipe size. Liquid line determined at 0°F evap. & 80°F cond. Discharge lines at 0°F evap.
Page 94 Tons of Refrigeration BTU's Per HR NOTE: Pressure drops do not allow for pulsating flow. If flow is pulsating, use next larger pipe size. Liquid line determined at 0°F evap. & 80°F cond. Discharge lines at 0°F evap. Other conditions do not appreciably change result.
Page 95 A LOOK AT SERVICE SAFETY Tons of Refrigeration BTU's Per HR NOTE: Pressure drops do not allow for pulsating flow. If flow is pulsating, use next larger pipe size. 0.3 0.4 0.6 0.8 1 6 810 30 40 50 EXAMPLE: At 80°F Condenser 5.5 Tons at -40°F Evap.
Page 96 Tons of Refrigeration NOTE: Pressure drops do not allow for pulsating flow. If flow is pulsating, use next larger pipe size. Liquid line and discharge lines determined at -20°C evap. and 30°C cond. Other conditions do not appreciably change result. Vapor at evap. outlet assumed to be at 20°C.
Page 97 A LOOK AT SERVICE SAFETY Tons of Refrigeration NOTE: Pressure drops do not allow for pulsating flow. If flow is pulsating, use next larger pipe size. Liquid line and discharge lines determined at 0°F evap. and 80°F cond. Other conditions do not appreciably change result.
Page 98: Refrigerant Line Velocities
Refrigerant Line Velocities Tons of Refrigeration BTU's Per HR NOTE: Liquid line determined at 0°F evap. and 80°F cond. Discharge lines at 0°F evap. Net refrigeration for "Freon" 12 includes suction gas at 65°F. EXAMPLE: 5.5 Tons at -40°F Evap. 85°F Cond. At 80°F Condenser 1 /8 "...
Page 99 A LOOK AT SERVICE SAFETY Tons of Refrigeration BTU's Per HR NOTE: Liquid line determined at 0°F evap. and 80°F cond. Discharge lines at 0°F evap. Net refrigeration for "Freon" 22 includes suction gas at 65°F. EXAMPLE: 5.5 Tons at -40°F Evap. 85°F Cond. At 80°F Condenser 5 /8 "...
Page 100 Tons of Refrigeration BTU's Per HR NOTE: Liquid line determined at 0°F evap. and 80°F cond. Discharge lines at 0°F evap. Net refrigeration for "Freon" 502 includes suction gas at 65°F. EXAMPLE: 5.5 Tons at -40°F Evap. 85°F Cond. At 80°F Condenser 5 /8 "...
Page 101 A LOOK AT SERVICE SAFETY Kilowatts of Refrigeration EXAMPLE: 55 kW at -40°C Evap., 40°C Cond. At 30°C Condenser 1 /8 " Suction Line Velocity = 38 m/s 3 /8 " Liquid Line Velocity = 0.55 m/s At 40°C Condenser At 50°C Condenser NOTE: Liquid line and discharge lines determined at -20°C evap.
Page 102 Kilowatts of Refrigeration EXAMPLE: At 30°C Condenser 45 kW at -30°C Evap., 40°C Cond. 1 /8 " Suction Line Velocity = 18 m/s 3 /8 " Liquid Line Velocity = 0.37 m/s At 40°C Condenser At 50°C Condenser NOTE: Liquid line determined at -20°C evap. and 30°C cond. Discharge lines at -20°C evap.
Page 103: Service Valves
A liquid line drier should also be installed. installing. 4. A suction line ﬁlter/drier is recommended to Service valves on Tecumseh systems are “front protect the compressor. A suction accumulator seated” by turning the valve stem clockwise. This must be installed on those systems having closes the valve and opens the gauge port.
Page 104: System Cleanup And Compressor
The following outlines a process for compressor Pressure air cooled condenser. replacement and system clean-up for a system equipped with a Tecumseh compressor. You should Water cooled Discharge water °F + 10°F refer to the original equipment manufacturers Saturated evaporator pressure (OEM) service information.
Page 105 A LOOK AT SERVICE SAFETY Contamination). A single installation of liquid and Rubber refrigeration hoses are not satisfactory for temporarily hooking up the suction line ﬁl- suction line ﬁlter-driers should cleanup the system. ter-drier to the system since the acid quickly If, however, the discharge line or the suction line breaks down the rubber and plastic.
Page 106 D. Charge the System and Check the In the case of Compressor Housing Contamination, little change should be noted. The pressure drop Pressure Drop will, in most instances, be below that tolerable for a Charge the system and place in operation. Follow permanent installation (see Table 5-3).
Page 107 A LOOK AT SERVICE SAFETY tem is free of acid. A reading of higher than 0.05 F. Test for Acidity If Multiple Motor Failures means continued cleaning is required. Return to B2 Have Occurred on page 105. If the system has suffered multiple motor failures, it is advisable that the oil of the replacement be tested after Section E and judged acid free before the sys- G.
Page 108: Replacing Compressors In Water-Utilizing Systems: Preventing Explosions
• water source heat pump/air conditioning sys- VIII. Replacing Compressors in tems, and Water-Utilizing Systems: • water cooling systems, such as icemakers, water Preventing Explosions coolers, and juice dispensers. In certain water-utilizing refrigeration systems, Water-utilizing systems that have single-wall heat water can leak into the refrigerant side of the system.
Page 109 A LOOK AT SERVICE SAFETY OPERATION Control of Liquid Migration to the Compressor During Shutdown ..110 Crankcase Heaters ....113 III.
Page 110: Control Of Liquid Migration To The Compressor During Shutdown
Control of Liquid Migration to (see Figures 6-2 to 6-4) were taken in the engineer- ing laboratories of Tecumseh Products Company. A the Compressor During ﬁve ton split air conditioning system was used with Shutdown a four inch sight glass installed in the compressor housing.
Page 111 A LOOK AT SERVICE SAFETY Figure 6-2. Refrigerant and oil mixture ﬁll sight glass after week-end shutdown. Figure 6-3. Five seconds after start-up, violent foaming action ﬁlls sight glass as refrigerant boils away taking oil charge with it. Figure 6-4. More than 60 seconds after start-up, oil level is well below normal operating levels—a condition that is an important...
Page 112 B. Crankcase Heater Prevents Liquid Migration This sequence (see Figures 6-6 and 6-7) shows the effects of an electric strap-on crankcase heater applied to the compressor (also see Figure 6-5). The system was again shutdown for a week-end under identical conditions, with the exception that the heater was energized throughout the shutdown period.
Page 113: Crankcase Heaters
• Contactor or thermostat breaks only one leg to Three types of crankcase heaters are in common use the compressor (and condenser fan). on Tecumseh compressors: wrap-around resistance • Equipment should carry a notice indicating heater (belly band), immersion type integral heater, and the run capacitance off-cycle heat.
Page 114: Starting A System With Liquid Refrigerant In The Compressor
• If there is no evidence of a compressor electrical III. Starting a System with Liquid problem (for example, tripped breaker or Refrigerant in the blown fuse, or reports of such), then “jog” the Compressor compressor. To “jog” the compressor apply power for one to two seconds, then wait 1 to 2 When most air conditioning and commercial sys- minutes.
Page 115: Control Of Liquid Refrigerant Floodback To The Compressor During Operation
A LOOK AT SERVICE SAFETY Control of Liquid Refrigerant erant. This separation result accumulation of the refrigerant under the oil (see Floodback to the Compressor Figure 6-10). Thus, when the compressor is started, During Operation the first liquid to be pumped to the bearings will probably be refrigerant, not oil.
Page 116 Figure 6-10. Liquid refrigerant enters compressor and settles to the bottom, below the oil. Figure 6-11. Five seconds after start-up, violent foaming action ﬁlls sight glass as refrigerant boils away taking the oil charge with it. Figure 6-12. More than 60 seconds after start-up, oil level is well below normal operating levels—a condition that is an important factor in compressor bearing wear.
Page 117 (see Figures 6-13 and 6-14 below and “Accumulator caused by liquid migration to the compressor during Selection Data” on page 118). Tecumseh engineers have periods of shutdown. This condition can be controlled designed a suction line accumulator available in eight by the application of a crankcase heater.
Page 118: Accumulator Selection
Accumulator Selection tor temperature and capacity in tons of refrigeration. These factors were considered in the design and test- Selecting the proper size is of primary importance. ing of the accumulator. Only one factor need be considered in order to assure the correct accumulator for a particular sys- If on older systems, the system refrigerant charge is tem: the total refrigerant charge in that system.
Page 119: Internal Pressure Relief Valves
A LOOK AT SERVICE SAFETY Internal Pressure Relief The IPR valve may also open to relieve hydraulic pressures in the event of slugging. This is apt to Valves occur on startup if refrigerant has been allowed to Certain air conditioning compressors in the AJ, AB, migrate to the compressor crankcase.
Page 120 Chapter 6...
Page 121 The Basic Refrigeration Cycle ..122 Example of a Tecumseh Hermetic Compressor ..... . 124 III.
Page 122: The Basic Refrigeration Cycle
The Basic Refrigeration Cycle bulb located at the evaporator outlet. In any case, the ﬂow of refrigerant into the evaporator normally Mechanical refrigeration is accomplished by contin- increases as the evaporator load increases. uously circulating, evaporating, and condensing a ﬁxed supply of refrigerant in a closed system. Evapo- As the high pressure liquid refrigerant enters the ration occurs at a low temperature and low pressure evaporator, it is subjected to a much lower pressure...
Page 123 High (Pressure) Side Liquid Line Value Suction Condenser Hermetic Compressor Condenser Discharge Receiver Pressure Tank Cutout Heat Exchanger Crankcase Accumulator Heater X X X X X X X X X X X X X X X X T-X Valve Sensor Bulb Evaporator Fan Expansion Valve or...
Page 124: Example Of A Tecumseh Hermetic Compressor
These compressor hous- ings are not normally subjected to discharge pressure The major internal parts of a Tecumseh hermetic — operating instead at relatively low suction pres- compressor are shown in Figure A-2 and are listed in sures.
Page 125 A LOOK AT SERVICE SAFETY Figure A-2. Internal view of typical air conditioning compressor. Appendix...
Page 126: Capillary Tube Sizing
III. Capillary Tube Sizing A. Suggested Capillary Tube Data for Domestic and Commercial Refrigeration Applications The following suggestions in Tables A-1 and A-2 assume a minimum of 36” heat exchange with the suction line and no subcooling in the liquid line immediately before the capillary tube.
Page 127 A LOOK AT SERVICE SAFETY Table A-2: R-12, R-134a, and R-404A Medium & High Temperature Normal Evaporating Temperature Compressor Capacity BTU/Hr. Condenser Type +15° to +20°F +20° to +35°F +35° to +50°F 1400-1600 12’ - .036 8’ - .036 8’ - .042 1600-1800 10’...
Page 128 The suggested capillary size is based on a condens- Example No. 2 (See Table A-3) ing temperature of 130°F, with 115°F liquid enter- Select the capillary required for a Tecumseh com- ing the capillary, 65°F gas entering the compressor. pressor AG5561E rated 61,000 BTU/Hr.
Page 129: Approved Hermetic Compressor Oils
The approved and alternate oils are as follows: charge contributes materially to successful compres- sor operation and long service life. Tecumseh Products Company has determined the optimum oil charge for each of its compressors, and Table A-4: Approved and Alternate this amount is speciﬁed on the compressor bill of...
Page 130 Table A-5: Oil Types to be Used in Compressor Families Compressor Families Source AZ AE AK AJ AH AB AW AV AG AN RK RG SF SA TH TP Napthenic •+ Witco-Suniso 1GS • • • • • • • •...
Page 131 A LOOK AT SERVICE SAFETY Table A-6: Oil Charge for Compressor Families Compressor Family Oil Charge (oz) AB (all) AEA 1360/80/10 AE (all others) AHA2466/80 AH (all others) AWA 2XXX, 7XXX, 9XXX AWE (all others) AWF (all others) AWG/J (all others) AZA/320/26/40 AZA/335/50 AZ (all others)
Page 132 Appendix...

Tecumseh AEA4440YXA Service Data Book

1 General Service Safety Precautions

3 Compressor Motor and Component Information

5 Installation and Replacement Information

6 Operation

Quick Links

Chapters

Related Manuals for Tecumseh AEA4440YXA

Summary of Contents for Tecumseh AEA4440YXA

Table of Contents