CHAPTER 1 I N T R O D U C T I O N
R E P O R T I N G E Q U I P M E N T I M P R O V E M E N T R E C O M M E N D A T I O N S ( E I R S)
CAPABILITIES AND FEATURES
E Q U I P M E N T D A TA
Section Ill. TECHNICAL PRINCIPLES OF OPERATION
ELECTRICAL SEQUENCE OF OPERATION
MODEL UH-68G
SCHEMATIC
CHAPTER 2 OPERATING INSTRUCTIONS
Table 2-1. Controls and Indicators-Continued
Section Il. OPERATOR PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS)
Table 2-2. Operator Preventive Maintenance Checks and Services
Table 2-2. Operator Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_21
Table 2-2. Operator Preventive Maintenance Checks and Services-Continued
Table 2-2. Operator Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_23
SECTION Ill. OPERATION UNDER USUAL CONDITIONS
O P E R A T I O N I N H E A T I N G M O DE
OPERATION IN FAN MODE
INFORMATION PLATES AND DECALS
INFORMATION PLATES AND DECALS CONT.
INFORMATION PLATES AND DECALS CONT. - TM-5-4520-253-13_29
INFORMATION PLATES AND DECALS CONT. - TM-5-4520-253-13_30
INFORMATION PLATES AND DECALS CONT.\
INFORMATION PLATES AND DECALS CONT. - TM-5-4520-253-13_32
SECTION IV. OPERATION UNDER UNUSUAL CONDITIONS - TM-5-4520-253-13_33
CHAPTER 3 UNIT MAINTENANCE INSTRUCTIONS
Section Il. REPAIR PARTS, SPECIAL TOOLS, TEST MEASUREMENT DIAGNOSTIC EQUIPMENT (TMDE), AND SUPPORT EQUIPMENT
M O U N T E D P O S I T I O N O F H E A T ER
R I G H T S I D E M O U N T I NG
A D D I T I O N A L I T E M S R E Q U I R ED
LOCATION OF HEATER
I N S T A L L A T I ON
I N S T A L L A T I ON CONT.
P R E L I M I N A R Y S E R V I C I N G A N D A D J U S T M E N T O F H E A T ER
PREVENTIVE MAINTENANCE CHECKS AND SERVICES - TM-5-4520-253-13_43
Table 3-2. Unit Preventive Maintenance Checks and Services
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_45
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_46
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_47
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_48
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_49
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_50
Section V. TROUBLESHOOTING
Table 3-3. Unit Maintenance Troubleshooting
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_53
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_54
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_55
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_56
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_57
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_58
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_59
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_60
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_61
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_62
S e c t i o n V I . M A I N T E N A N C E P R O C E D U R E S
CONTROL BOX ASSEMBLY PROCEDURES INDEX
INSPECT/REMOVE/lNSTALL CONTROL BOX (CONT)
l N S P E C T / R E M O V E / l N S T A L L R O O M T H E R M O S T A T R E C E P T A C LE
lNSPECT/REMOVE/lNSTALL ROOM THERMOSTAT RECEPTACLE (CONT) - TM-5-4520-253-13_67
lNSPECT/REMOVE/lNSTALL ROOM THERMOSTAT RECEPTACLE (CONT) - TM-5-4520-253-13_68
l N S P E C T / T E S T / R E M O V E / l N S T A L L C I R C U I T B R E A K ER
l N S P E C T / T E S T / R E M O V E / l N S T A L L C I R C U I T B R E A K E R ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L R E S E T C I R C U I T B R E A K ER
l N S P E C T / T E S T / R E M O V E / l N S T A L L R E S E T C I R C U I T B R E A K E R ( C O N T)
I N S P E C T C O N T R O L B O X W I R I N G H A R N E SS
REPAIR CONTROL BOX HARNESS PLUG
REPAIR CONTROL BOX HARNESS PLUG (CONT) - TM-5-4520-253-13_75
REPAIR CONTROL BOX HARNESS PLUG (CONT) - TM-5-4520-253-13_76
REPAIR WIRE TERMINALS
R E P A I R W I R E T E R M I N A L S ( C O N T)
REPLACE CONTROL BOX HARNESS WIRES
REPLACE CONTROL BOX HARNESS WIRES (CONT) - TM-5-4520-253-13_80
REPLACE CONTROL BOX HARNESS WIRES (CONT) - TM-5-4520-253-13_81
REPLACE CONTROL BOX HARNESS WIRES (CONT) - TM-5-4520-253-13_82
l N S P E C T / T E S T / R E M O V E / l N S T A L L H E A T E R - O F F - F A N S W I T CH
l N S P E C T / T E S T / R E M O V E / l N S T A L L H E A T E R - O F F - F A N S W I T C H ( C O N T)
l N S P E C T / T E S T / R E M O V E / l N S T A L L H E A T E R - O F F - F A N S W I T C H ( C O N T)
R E M O V E / l N S T A L L H E A T A N D F A U L T L I G H TS
REMOVE/lNSTALL HEAT AND FAULT LIGHTS (CONT)
l N S P E C T / R E M O V E / l N S T A L L P O W E R R E C E P T A C L E A N D E X T E R N A L F U EL P U M P R E C E P T A C LE
lNSPECT/REMOVE/INSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT)
lNSPECT/REMOVE/lNSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT) - TM-5-4520-253-13_90
lNSPECT/REMOVE/lNSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT) - TM-5-4520-253-13_91
lNSPECT/REMOVE/lNSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT) - TM-5-4520-253-13_92
INSPECT PRINTED CIRCUIT (PC) BOARD ASSEMBLY
HEATER CASE ASSEMBLY PROCEDURES INDEX
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L D O O R S A N D B O T T O M C O V E R\
A D J U S T / I N S P E C T / S E R V I C E / R E M O V E / l N S T A L L D O O R S A N D B O T T O M C O V E R ( C O N T)
ADJUST/lNSPECT/SERVICE/REMOVE/lNSTALL DOORS AND B O T T O M C O V E R ( C O N T) - TM-5-4520-253-13_106
ADJUST/lNSPECT/SERVICE/REMOVE/lNSTALL DOORS AND B O T T O M C O V E R ( C O N T) - TM-5-4520-253-13_107
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S ( C O N T )
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S ( C O N T)
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S ( C O N T)
l N S P E C T / R E M O V E / l N S T A L L L A B E L S
FUEL SYSTEM PROCEDURES INDEX
l N S P E C T / R E P A I R / R E M O V E / 2. 3. 4. 5. INSTALL FUEL LINES AND FITTINGS (CONT)
l N S P E C T / R E P A I R / R E M O V E / l N S T A L L F U E L L I N E S A N D F I T T I N G S ( C O N T )
l N S P E C T / R E P A I R / R E M O V E / l N S T A L L F U E L L I N E S A N D F I T T I N G S ( C O N T )
SERVICE/REMOVE/lNSTALL FUEL FILTER
S E R V I C E / R E M O V E / l N S T A L L F U E L F I L T E R ( C O N T)
S E R V I C E / R E M O V E / l N S T A L L F U E L F I L T E R ( C O N T)
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_121
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_122
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_123
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_124
l N S P E C T / T E S T / R E M O V E / l N S T A L L S O L E N O ID
l N S P E C T / T E S T / R E M O V E / l N S T A L L S O L E N O I D ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S O L E N O I D ( C O N T )
ELECTRICAL PROCEDURES INDEX - TM-5-4520-253-13_128
I N S P E C T C O M B U S T I O N B L O W E R ( C O N T)
I N S P E C T V E N T I L A T I N G A I R M O T OR
I N S P E C T V E N T I L A T I N G A I R M O T O R ( C O N T) - TM-5-4520-253-13_131
I N S P E C T V E N T I L A T I N G A I R M O T O R ( C O N T) - TM-5-4520-253-13_132
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A ME S W I T C H A N D B R A C K E T A S S E M B LY
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
BURNER ASSEMBLY PROCEDURES INDEX
R E M O V E / l N S T A L L / T E S T / R E P A I R I G N I T I O N T R A N S F O R M E R A N D C A B L E ( C O N T)
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_140
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_141
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_142
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_143
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_144
S E R V I C E / T E S T / R E M O V E / l N S T A L L I G N I T E R A S S E M B L Y
S E R V I C E / T E S T / R E M O V E / l N S T A L L I G N I T E R A S S E M B L Y ( C O N T)
S E R V I C E / T E S T / R E M O V E / l N S T A L L I G N I T E R A S S E M B L Y ( C O N T)
ACCESSORY ITEMS PROCEDURES INDEX
T E S T / A D J U S T / R E M O V E / l N S T A L L R O O M T H E R M O S T A T ( C O N T)
T E S T / A D J U S T / R E M O V E / l N S T A L L R O O M T H E R M O S T A T ( C O N T)
R E M O V E / l N S T A L L S I D E H E A T E R C A S E C O V E RS
R E N I O V E / l N S T A L L P O W E R , F U E L P U M P , A N D R O O M T H E R M O S T A T P L U GS
R E M O V E / l N S T A L L P O W E R , F U E L P U M P , A N D R O O M T H E R M O S T AT PLUGS (CONT)
R E M O V E / l N S T A L L P O W E R , F U E L P U M P , A N D R O O M T H E R M O S T AT PLUGS (CONT)
P R E P A R A T I ON
P A C K A G I N G
C H A P T E R 4 I N T E R M E D I A T E M A I N T E N A N C E I N S T R U C T I O NS
Table 4-1. Intermediate Maintenance Troubleshooting
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_159
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_160
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_161
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_162
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_163
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_164
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_165
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_166
Section II. MAINTENANCE PROCEDURES
PRINTED CIRCUIT (PC) BOARD ASSEMBLY PROCEDURES INDEX
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT)
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_170
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT)\
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_172
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_173
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_174
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_175
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_176
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_177
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_178
R E P A I R P C B O A R D A S S E M B L Y W I R I N G R E C E P T A C LE
REPAIR PC BOARD ASSEMBLY WIRING RECEPTACLE (CONT) - TM-5-4520-253-13_180
REPAIR PC BOARD ASSEMBLY WIRING RECEPTACLE (CONT) - TM-5-4520-253-13_181
R E P A I R P C B O A R D A S S E M B L Y W I R I N G T E R M I N A LS
REPAIR PC BOARD ASSEMBLY WIRING 5. 6. TERMINALS (CONT) - TM-5-4520-253-13_183
REPAIR PC BOARD ASSEMBLY WIRING 5. 6. TERMINALS (CONT) - TM-5-4520-253-13_184
REPAIR PC BOARD ASSEMBLY HARNESS RECEPTACLE AND PLUG
REPAIR PC BOARD ASSEMBLY HARNESS RECEPTACLE AND PLUG (CONT) - TM-5-4520-253-13_186
REPAIR PC BOARD ASSEMBLY HARNESS RECEPTACLE AND PLUG (CONT) - TM-5-4520-253-13_187
TEST PC BOARD A S S E M B L Y
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_189
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_190
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_191
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_192
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_193
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_194
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_195
HEATER CASE ASSEMBLY REPAIR PROCEDURES INDEX
DISASSEMBLE/ASSEMBLE HEATER CASE ASSEMBLY (CONT)
G E N E R A L R E P A I R H E A T E R C A S E A S S E M B LY
GENERAL REPAIR HEATER CASE ASSEMBLY (CONT)
REMOVE/lNSTALL SHIELDS AND SHIELD INSULATOR
REMOVE/lNSTALL SHIELDS AND SHIELD INSULATOR (CONT)
R E P A I R P A I N T E D S U R F A C ES
ELECTRICAL PROCEDURES INDEX - TM-5-4520-253-13_203
R E M O V E / I N S T A LL TM 5-4520-253-13 C O M B U S T I O N B L O W E R A N D H O U S I N G ( C O N T)
R E M O V E / l N S T A L L C O M B U S T I O N B L O W E R A N D H O U S I N G ( C O N T)
R E M O V E / I N S T A L L C O M B U S T I O N B L O W E R A N D H O U S I N G ( C O N T)
REMOVE/lNSTALL/TEST THERMAL MOTOR PROTECTOR
REMOVE/lNSTALL/TEST THERMAL MOTOR PROTECTOR CONT.
REMOVE/lNSTALL/TEST CAPACITORS
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR (CONT) - TM-5-4520-253-13_211
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR (CONT) - TM-5-4520-253-13_212
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR (CONT) - TM-5-4520-253-13_213
R E P A I R B L O W E R M O T OR
R E P A I R B L O W E R M O T O R ( C O N T)
R E M O V E / l N S T A L L V E N T I L A T I N G A I R M O T O R
REMOVE/lNSTALL VENTILATING AIR MOTOR (CONT) - TM-5-4520-253-13_217
REMOVE/lNSTALL VENTILATING AIR MOTOR (CONT) - TM-5-4520-253-13_218
REMOVE/lNSTALL VENTILATING AIR MOTOR (CONT) - TM-5-4520-253-13_219
R E M O V E / l N S T A L L V E N T I L A T I N G A I R M O T O R ( C O N T)
T E S T V E N T I L A T I N G A I R M O T OR
TEST VENTILATING AIR MOTOR (CONT)
T E S T V E N T I L A T I N G A I R M O T O R C A P A C I T O R
T E S T V E N T I L A T I N G A I R M O T O R C A P A C I T O R ( C O N T)
BURNER HEAD ASSEMBLY PROCEDURES INDEX
REMOVE/lNSTALL BURNER HEAD ASSEMBLY (CONT) - TM-5-4520-253-13_226
REMOVE/lNSTALL BURNER HEAD ASSEMBLY (CONT) - TM-5-4520-253-13_227
R E P A IR TOOLS: B U R N E R H E A D A S S E M B LY
REPAIR BURNER HEAD ASSEMBLY (CONT)
HEAT EXCHANGER PROCEDURES INDEX
REMOVE/lNSTALL HEAT EXCHANGER (CONT) - TM-5-4520-253-13_231
REMOVE/lNSTALL HEAT EXCHANGER (CONT)
REMOVE/lNSTALL HEAT EXCHANGER (CONT) - TM-5-4520-253-13_233
REMOVE/lNSTALL HEAT EXCHANGER (CONT) - TM-5-4520-253-13_234
CLEAN/lNSPECT/REPAIR HEAT EXCHANGER
CLEAN/lNSPECT/REPAIR HEAT EXCHANGER (CONT)
A P P E N D I X A R E F E R E N C ES
A P P E N D I X B MAINTENANCE ALLOCATION CHART
USE OF THE MAINTENANCE ALLOCATION CHART, SECTION II
EXPLANATION OF COLUMNS IN THE MAC, SECTION II
EXPLANATION OF COLUMNS IN THE MAC, SECTION Ill
Section Il. MAINTENANCE ALLOCATION CHART Continued - TM-5-4520-253-13_242
Section Il. MAINTENANCE ALLOCATION CHART Continued - TM-5-4520-253-13_243
Section Il. MAINTENANCE ALLOCATION CHART Continued - TM-5-4520-253-13_244
Section Ill. TOOL AND TEST EQUIPMENT REQUIREMENTS
A P P E N D I X C C O M P O N E N T S O F E N D I T E M S A N D B A S I C I S S U E I T E M S L I ST
Section Il. INTEGRAL COMPONENTS OF END ITEM
Section Ill. BASIC ISSUE ITEMS
A P P E N D I X D ADDITIONAL AUTHORIZATION LIST
Section Il. ADDITIONAL AUTHORIZATION LIST
A P P E N D I X E EXPENDABLE SUPPLIES AND MATERIALS LIST
Section Il. EXPENDABLE SUPPLIES AND MATERIALS LIST - TM-5-4520-253-13_252
A P P E N D I X F ILLUSTRATED LIST OF MANUFACTURED ITEMS
Figure 3. Wire No. 10795
Figure 5. Wire No. 10736
Figure 7. Wire No. 10781
Figure 9. Wire No. 10766
Figure 11. Wire No. 10739.
PART NUMBER INDEX
A P P E N D I X G TORQUE LIMITS
G L O S S A RY
G L O S S A RY CONT.
G L O S S A RY CONT. - TM-5-4520-253-13_263
G L O S S A RY CONT. - TM-5-4520-253-13_264
ALPHABETICAL INDEX
ALPHABETICAL INDEX CONT.
ALPHABETICAL INDEX CONT.
R E P O R T I N G E Q U I P M E N T I M P R O V E M E N T R E C O M M E N D A T I O N S ( E I R S)
CAPABILITIES AND FEATURES
E Q U I P M E N T D A TA
Section Ill. TECHNICAL PRINCIPLES OF OPERATION
ELECTRICAL SEQUENCE OF OPERATION
MODEL UH-68G
SCHEMATIC
CHAPTER 2 OPERATING INSTRUCTIONS
Table 2-1. Controls and Indicators-Continued
Section Il. OPERATOR PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS)
Table 2-2. Operator Preventive Maintenance Checks and Services
Table 2-2. Operator Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_21
Table 2-2. Operator Preventive Maintenance Checks and Services-Continued
Table 2-2. Operator Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_23
SECTION Ill. OPERATION UNDER USUAL CONDITIONS
O P E R A T I O N I N H E A T I N G M O DE
OPERATION IN FAN MODE
INFORMATION PLATES AND DECALS
INFORMATION PLATES AND DECALS CONT.
INFORMATION PLATES AND DECALS CONT. - TM-5-4520-253-13_29
INFORMATION PLATES AND DECALS CONT. - TM-5-4520-253-13_30
INFORMATION PLATES AND DECALS CONT.\
INFORMATION PLATES AND DECALS CONT. - TM-5-4520-253-13_32
SECTION IV. OPERATION UNDER UNUSUAL CONDITIONS - TM-5-4520-253-13_33
CHAPTER 3 UNIT MAINTENANCE INSTRUCTIONS
Section Il. REPAIR PARTS, SPECIAL TOOLS, TEST MEASUREMENT DIAGNOSTIC EQUIPMENT (TMDE), AND SUPPORT EQUIPMENT
M O U N T E D P O S I T I O N O F H E A T ER
R I G H T S I D E M O U N T I NG
A D D I T I O N A L I T E M S R E Q U I R ED
LOCATION OF HEATER
I N S T A L L A T I ON
I N S T A L L A T I ON CONT.
P R E L I M I N A R Y S E R V I C I N G A N D A D J U S T M E N T O F H E A T ER
PREVENTIVE MAINTENANCE CHECKS AND SERVICES - TM-5-4520-253-13_43
Table 3-2. Unit Preventive Maintenance Checks and Services
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_45
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_46
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_47
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_48
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_49
Table 3-2. Unit Preventive Maintenance Checks and Services-Continued - TM-5-4520-253-13_50
Section V. TROUBLESHOOTING
Table 3-3. Unit Maintenance Troubleshooting
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_53
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_54
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_55
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_56
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_57
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_58
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_59
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_60
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_61
Table 3-3. Unit Maintenance Troubleshooting Continued - TM-5-4520-253-13_62
S e c t i o n V I . M A I N T E N A N C E P R O C E D U R E S
CONTROL BOX ASSEMBLY PROCEDURES INDEX
INSPECT/REMOVE/lNSTALL CONTROL BOX (CONT)
l N S P E C T / R E M O V E / l N S T A L L R O O M T H E R M O S T A T R E C E P T A C LE
lNSPECT/REMOVE/lNSTALL ROOM THERMOSTAT RECEPTACLE (CONT) - TM-5-4520-253-13_67
lNSPECT/REMOVE/lNSTALL ROOM THERMOSTAT RECEPTACLE (CONT) - TM-5-4520-253-13_68
l N S P E C T / T E S T / R E M O V E / l N S T A L L C I R C U I T B R E A K ER
l N S P E C T / T E S T / R E M O V E / l N S T A L L C I R C U I T B R E A K E R ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L R E S E T C I R C U I T B R E A K ER
l N S P E C T / T E S T / R E M O V E / l N S T A L L R E S E T C I R C U I T B R E A K E R ( C O N T)
I N S P E C T C O N T R O L B O X W I R I N G H A R N E SS
REPAIR CONTROL BOX HARNESS PLUG
REPAIR CONTROL BOX HARNESS PLUG (CONT) - TM-5-4520-253-13_75
REPAIR CONTROL BOX HARNESS PLUG (CONT) - TM-5-4520-253-13_76
REPAIR WIRE TERMINALS
R E P A I R W I R E T E R M I N A L S ( C O N T)
REPLACE CONTROL BOX HARNESS WIRES
REPLACE CONTROL BOX HARNESS WIRES (CONT) - TM-5-4520-253-13_80
REPLACE CONTROL BOX HARNESS WIRES (CONT) - TM-5-4520-253-13_81
REPLACE CONTROL BOX HARNESS WIRES (CONT) - TM-5-4520-253-13_82
l N S P E C T / T E S T / R E M O V E / l N S T A L L H E A T E R - O F F - F A N S W I T CH
l N S P E C T / T E S T / R E M O V E / l N S T A L L H E A T E R - O F F - F A N S W I T C H ( C O N T)
l N S P E C T / T E S T / R E M O V E / l N S T A L L H E A T E R - O F F - F A N S W I T C H ( C O N T)
R E M O V E / l N S T A L L H E A T A N D F A U L T L I G H TS
REMOVE/lNSTALL HEAT AND FAULT LIGHTS (CONT)
l N S P E C T / R E M O V E / l N S T A L L P O W E R R E C E P T A C L E A N D E X T E R N A L F U EL P U M P R E C E P T A C LE
lNSPECT/REMOVE/INSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT)
lNSPECT/REMOVE/lNSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT) - TM-5-4520-253-13_90
lNSPECT/REMOVE/lNSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT) - TM-5-4520-253-13_91
lNSPECT/REMOVE/lNSTALL POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE (CONT) - TM-5-4520-253-13_92
INSPECT PRINTED CIRCUIT (PC) BOARD ASSEMBLY
HEATER CASE ASSEMBLY PROCEDURES INDEX
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
l N S P E C T / S E R V I C E H E A T E R C A S E A S S E M B L Y ( C O N T )
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L S I D E P A N E L S A ND LOUVER LINKAGE (CONT]
A D J U S T / l N S P E C T / S E R V I C E / R E M O V E / l N S T A L L D O O R S A N D B O T T O M C O V E R\
A D J U S T / I N S P E C T / S E R V I C E / R E M O V E / l N S T A L L D O O R S A N D B O T T O M C O V E R ( C O N T)
ADJUST/lNSPECT/SERVICE/REMOVE/lNSTALL DOORS AND B O T T O M C O V E R ( C O N T) - TM-5-4520-253-13_106
ADJUST/lNSPECT/SERVICE/REMOVE/lNSTALL DOORS AND B O T T O M C O V E R ( C O N T) - TM-5-4520-253-13_107
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S ( C O N T )
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S ( C O N T)
l N S P E C T / R E M O V E / l N S T A L L D A T A P L A T E S ( C O N T)
l N S P E C T / R E M O V E / l N S T A L L L A B E L S
FUEL SYSTEM PROCEDURES INDEX
l N S P E C T / R E P A I R / R E M O V E / 2. 3. 4. 5. INSTALL FUEL LINES AND FITTINGS (CONT)
l N S P E C T / R E P A I R / R E M O V E / l N S T A L L F U E L L I N E S A N D F I T T I N G S ( C O N T )
l N S P E C T / R E P A I R / R E M O V E / l N S T A L L F U E L L I N E S A N D F I T T I N G S ( C O N T )
SERVICE/REMOVE/lNSTALL FUEL FILTER
S E R V I C E / R E M O V E / l N S T A L L F U E L F I L T E R ( C O N T)
S E R V I C E / R E M O V E / l N S T A L L F U E L F I L T E R ( C O N T)
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_121
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_122
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_123
lNSPECT/SERVICE/ADJUST/REMOVE/lNSTALL CARBURETOR CONT - TM-5-4520-253-13_124
l N S P E C T / T E S T / R E M O V E / l N S T A L L S O L E N O ID
l N S P E C T / T E S T / R E M O V E / l N S T A L L S O L E N O I D ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S O L E N O I D ( C O N T )
ELECTRICAL PROCEDURES INDEX - TM-5-4520-253-13_128
I N S P E C T C O M B U S T I O N B L O W E R ( C O N T)
I N S P E C T V E N T I L A T I N G A I R M O T OR
I N S P E C T V E N T I L A T I N G A I R M O T O R ( C O N T) - TM-5-4520-253-13_131
I N S P E C T V E N T I L A T I N G A I R M O T O R ( C O N T) - TM-5-4520-253-13_132
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A ME S W I T C H A N D B R A C K E T A S S E M B LY
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
l N S P E C T / T E S T / R E M O V E / l N S T A L L S A F E T Y T H E R M O S T A T S A N D F L A M E S W I T C H A N D B R A C K E T A S S E M B L Y ( C O N T )
BURNER ASSEMBLY PROCEDURES INDEX
R E M O V E / l N S T A L L / T E S T / R E P A I R I G N I T I O N T R A N S F O R M E R A N D C A B L E ( C O N T)
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_140
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_141
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_142
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_143
REMOVE/lNSTALL/TEST/REPAIR IGNITION TRANSFORMER AND CABLE (CONT) - TM-5-4520-253-13_144
S E R V I C E / T E S T / R E M O V E / l N S T A L L I G N I T E R A S S E M B L Y
S E R V I C E / T E S T / R E M O V E / l N S T A L L I G N I T E R A S S E M B L Y ( C O N T)
S E R V I C E / T E S T / R E M O V E / l N S T A L L I G N I T E R A S S E M B L Y ( C O N T)
ACCESSORY ITEMS PROCEDURES INDEX
T E S T / A D J U S T / R E M O V E / l N S T A L L R O O M T H E R M O S T A T ( C O N T)
T E S T / A D J U S T / R E M O V E / l N S T A L L R O O M T H E R M O S T A T ( C O N T)
R E M O V E / l N S T A L L S I D E H E A T E R C A S E C O V E RS
R E N I O V E / l N S T A L L P O W E R , F U E L P U M P , A N D R O O M T H E R M O S T A T P L U GS
R E M O V E / l N S T A L L P O W E R , F U E L P U M P , A N D R O O M T H E R M O S T AT PLUGS (CONT)
R E M O V E / l N S T A L L P O W E R , F U E L P U M P , A N D R O O M T H E R M O S T AT PLUGS (CONT)
P R E P A R A T I ON
P A C K A G I N G
C H A P T E R 4 I N T E R M E D I A T E M A I N T E N A N C E I N S T R U C T I O NS
Table 4-1. Intermediate Maintenance Troubleshooting
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_159
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_160
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_161
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_162
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_163
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_164
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_165
Table 4-1. Intermediate Maintenance Troubleshooting Continued - TM-5-4520-253-13_166
Section II. MAINTENANCE PROCEDURES
PRINTED CIRCUIT (PC) BOARD ASSEMBLY PROCEDURES INDEX
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT)
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_170
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT)\
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_172
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_173
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_174
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_175
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_176
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_177
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_178
R E P A I R P C B O A R D A S S E M B L Y W I R I N G R E C E P T A C LE
REPAIR PC BOARD ASSEMBLY WIRING RECEPTACLE (CONT) - TM-5-4520-253-13_180
REPAIR PC BOARD ASSEMBLY WIRING RECEPTACLE (CONT) - TM-5-4520-253-13_181
R E P A I R P C B O A R D A S S E M B L Y W I R I N G T E R M I N A LS
REPAIR PC BOARD ASSEMBLY WIRING 5. 6. TERMINALS (CONT) - TM-5-4520-253-13_183
REPAIR PC BOARD ASSEMBLY WIRING 5. 6. TERMINALS (CONT) - TM-5-4520-253-13_184
REPAIR PC BOARD ASSEMBLY HARNESS RECEPTACLE AND PLUG
REPAIR PC BOARD ASSEMBLY HARNESS RECEPTACLE AND PLUG (CONT) - TM-5-4520-253-13_186
REPAIR PC BOARD ASSEMBLY HARNESS RECEPTACLE AND PLUG (CONT) - TM-5-4520-253-13_187
TEST PC BOARD A S S E M B L Y
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_189
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_190
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_191
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_192
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_193
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_194
TEST PC BOARD ASSEMBLY (CONT) - TM-5-4520-253-13_195
HEATER CASE ASSEMBLY REPAIR PROCEDURES INDEX
DISASSEMBLE/ASSEMBLE HEATER CASE ASSEMBLY (CONT)
G E N E R A L R E P A I R H E A T E R C A S E A S S E M B LY
GENERAL REPAIR HEATER CASE ASSEMBLY (CONT)
REMOVE/lNSTALL SHIELDS AND SHIELD INSULATOR
REMOVE/lNSTALL SHIELDS AND SHIELD INSULATOR (CONT)
R E P A I R P A I N T E D S U R F A C ES
ELECTRICAL PROCEDURES INDEX - TM-5-4520-253-13_203
R E M O V E / I N S T A LL TM 5-4520-253-13 C O M B U S T I O N B L O W E R A N D H O U S I N G ( C O N T)
R E M O V E / l N S T A L L C O M B U S T I O N B L O W E R A N D H O U S I N G ( C O N T)
R E M O V E / I N S T A L L C O M B U S T I O N B L O W E R A N D H O U S I N G ( C O N T)
REMOVE/lNSTALL/TEST THERMAL MOTOR PROTECTOR
REMOVE/lNSTALL/TEST THERMAL MOTOR PROTECTOR CONT.
REMOVE/lNSTALL/TEST CAPACITORS
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR (CONT) - TM-5-4520-253-13_211
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR (CONT) - TM-5-4520-253-13_212
DISASSEMBLE/ASSEMBLE/TEST BLOWER MOTOR (CONT) - TM-5-4520-253-13_213
R E P A I R B L O W E R M O T OR
R E P A I R B L O W E R M O T O R ( C O N T)
R E M O V E / l N S T A L L V E N T I L A T I N G A I R M O T O R
REMOVE/lNSTALL VENTILATING AIR MOTOR (CONT) - TM-5-4520-253-13_217
REMOVE/lNSTALL VENTILATING AIR MOTOR (CONT) - TM-5-4520-253-13_218
REMOVE/lNSTALL VENTILATING AIR MOTOR (CONT) - TM-5-4520-253-13_219
R E M O V E / l N S T A L L V E N T I L A T I N G A I R M O T O R ( C O N T)
T E S T V E N T I L A T I N G A I R M O T OR
TEST VENTILATING AIR MOTOR (CONT)
T E S T V E N T I L A T I N G A I R M O T O R C A P A C I T O R
T E S T V E N T I L A T I N G A I R M O T O R C A P A C I T O R ( C O N T)
BURNER HEAD ASSEMBLY PROCEDURES INDEX
REMOVE/lNSTALL BURNER HEAD ASSEMBLY (CONT) - TM-5-4520-253-13_226
REMOVE/lNSTALL BURNER HEAD ASSEMBLY (CONT) - TM-5-4520-253-13_227
R E P A IR TOOLS: B U R N E R H E A D A S S E M B LY
REPAIR BURNER HEAD ASSEMBLY (CONT)
HEAT EXCHANGER PROCEDURES INDEX
REMOVE/lNSTALL HEAT EXCHANGER (CONT) - TM-5-4520-253-13_231
REMOVE/lNSTALL HEAT EXCHANGER (CONT)
REMOVE/lNSTALL HEAT EXCHANGER (CONT) - TM-5-4520-253-13_233
REMOVE/lNSTALL HEAT EXCHANGER (CONT) - TM-5-4520-253-13_234
CLEAN/lNSPECT/REPAIR HEAT EXCHANGER
CLEAN/lNSPECT/REPAIR HEAT EXCHANGER (CONT)
A P P E N D I X A R E F E R E N C ES
A P P E N D I X B MAINTENANCE ALLOCATION CHART
USE OF THE MAINTENANCE ALLOCATION CHART, SECTION II
EXPLANATION OF COLUMNS IN THE MAC, SECTION II
EXPLANATION OF COLUMNS IN THE MAC, SECTION Ill
Section Il. MAINTENANCE ALLOCATION CHART Continued - TM-5-4520-253-13_242
Section Il. MAINTENANCE ALLOCATION CHART Continued - TM-5-4520-253-13_243
Section Il. MAINTENANCE ALLOCATION CHART Continued - TM-5-4520-253-13_244
Section Ill. TOOL AND TEST EQUIPMENT REQUIREMENTS
A P P E N D I X C C O M P O N E N T S O F E N D I T E M S A N D B A S I C I S S U E I T E M S L I ST
Section Il. INTEGRAL COMPONENTS OF END ITEM
Section Ill. BASIC ISSUE ITEMS
A P P E N D I X D ADDITIONAL AUTHORIZATION LIST
Section Il. ADDITIONAL AUTHORIZATION LIST
A P P E N D I X E EXPENDABLE SUPPLIES AND MATERIALS LIST
Section Il. EXPENDABLE SUPPLIES AND MATERIALS LIST - TM-5-4520-253-13_252
A P P E N D I X F ILLUSTRATED LIST OF MANUFACTURED ITEMS
Figure 3. Wire No. 10795
Figure 5. Wire No. 10736
Figure 7. Wire No. 10781
Figure 9. Wire No. 10766
Figure 11. Wire No. 10739.
PART NUMBER INDEX
A P P E N D I X G TORQUE LIMITS
G L O S S A RY
G L O S S A RY CONT.
G L O S S A RY CONT. - TM-5-4520-253-13_263
G L O S S A RY CONT. - TM-5-4520-253-13_264
ALPHABETICAL INDEX
ALPHABETICAL INDEX CONT.
ALPHABETICAL INDEX CONT.
