SERVICING
19
Table of Contents
HIGH VOLTAGE!
Disconnect ALL power before servicing or installing this unit. Multiple power sources
may be present. Failure to do so may cause property damage, personal injury or death.
S-1 Checking Voltage .......................................... 20
S-2 Checking Wiring............................................ 21
S-3 Checking Thermostat, Wiring & Anticipator .. 21
S-3A Thermostat & Wiring ..................................... 21
S-3B Cooling Anticipator ........................................ 21
S-4 Checking Transformer & Control Circuit ....... 21
S-7 Checking Contactor and/or Relays................ 22
S-8 Checking Contactor Contacts ....................... 22
S-9 Checking Fan Relay Contact ........................ 23
S-11 Checking Loss of Charge Protection ............. 24
S-12 Checking High Pressure Control ................... 24
S-13 Checking Low Pressure Control .................... 24
S-15 Checking Capacitor ...................................... 25
S-15A Resistance Check ......................................... 25
S-15B Capacitance Check ...................................... 25
S-16 Checking Motors ........................................... 26
S-16A Checking Fan & Blower Motor
Windings (PSC Motors) ............................... 26
S-16D Checking EEM Motors .................................. 26
S-17 Checking Compressor Windings .................. 27
S-17A Resistance Test ............................................ 27
S-17B Ground Test .................................................. 27
S-17D Operation Test .............................................. 28
S-18 Testing Crankcase Heater (optional item) ..... 28
S-18A Crankcase Heater Thermostat ...................... 28
S-21 Checking Reversing Valve & Solenoid .......... 28
S-24 Testing Defrost Control ................................. 29
S-25 Testing Defrost Thermostat ........................... 29
S-50 Checking Heater Limit Control(s).................. 30
S-100 Refrigeration Repair Practice ....................... 30
S-101 Leak Testing ................................................. 30
S-102 Evacuation .................................................... 31
S-103 Charging....................................................... 32
S-104 Checking Compressor Efficiency ................. 33
S-106 Overfeeding .................................................. 33
S-108 Checking Superheat ..................................... 33
S-111 Fixed Orifice Restriction Devices.................. 36
S-112 Checking Restricted Liquid Line ................... 36
S-113 Refrigerant Overcharge ................................ 36
S-114 Non-condensables ........................................ 36
S-115 Compressor Burnout ..................................... 36
S-200 Checking External Static Pressure ............... 37
S-201 Checking Temperature Rise ......................... 39
S-205 Checking Belt Tension .................................. 38
S-206 Indoor Fan Rotation Check ........................... 39
S-207 Motor Sheave Adjustment ............................. 39