Carrier 38MVC, 38MVQ, 40MVC, 40MVQ CONNECTION DIAGRAMS

WIRING

The main power is supplied to the outdoor unit. The field supplied connecting cable from the outdoor unit to indoor unit consists of four

wires and provides the power for the indoor unit as well as the communication signal between the outdoor unit and indoor unit.

Voltage drop on the connecting cable should be kept to a minimum. Use cable size and max length below:

18 AWG 50 ft. (16 m)

16 AWG 100 ft. (33 m)

CONNECTION DIAGRAMS

CONNECTING CABLE

CONTROL CONTROL

Notes:

1. Do not use thermostat wire for any connection between indoor and outdoor units.

2. All connections between indoor and outdoor units must be as shown. The connections are sensitive to polarity.

3. On the 18k and 24k units, the “S” terminal “CONTROL” output is pulse DC with a potential AC voltage shock hazard.

A07654

Fig. 5 – Connection Diagrams

38/40MVC, MVQ

Contents

Main Service Manual SAFETY CONSIDERATIONS !WARNING INTRODUCTION MODEL NUMBER NOMENCLATURE OUTDOOR UNIT INDOOR UNIT SERIAL NUMBER NOMENCLATURE STANDARD FEATURES AND ACCESSORIES INDOOR UNITS 38/40MVC, MVQ OUTDOOR UNITS LOW AMBIENT KIT CRANKCASE HEATER SPECIFICATIONS -- COOLING ONLY UNITS 38/40MVC, MVQ SPECIFICATIONS -- HEAT PUMP UNITS DIMENSIONS -- INDOOR DIMENSIONS -- OUTDOOR H W L1 CLEARANCES -- INDOOR CLEARANCES -- OUTDOOR SYSTEM OPERATING ENVELOPE 38/40MVC, MVQ 53MVC/MVQ System Operating Envelope Chart Cooling Continuous Operation Heating Continuous Operation CONNECTION DIAGRAMS Page Page Page Page Page Page Page REFRIGERATION CYCLE DIAGRAM REFRIGERANT LINES SYSTEM EVACUATION AND CHARGING CAUTION t ! SYSTEM VACUUM AND CHARGE Outdoor Unit Indoor Uni CONTROL SYSTEM SYSTEM SAFETIES 3MINUTETIMEDELAY COMPRESSOR OVERCURRENT PROTECTION S S S S SEQUENCE OF OPERATION Interface MODES OF OPERATION Page Page TROUBLESHOOTING DIAGNOSTIC HIERARCHY CHART 1 -- INDOOR FAN SPEED OUT OF CONTROL CHART 2 -- TEMPERATURE SENSOR CHART 3 -- COMPRESSOR OVERCURRENT PROTECTION CHART 4 -- INDOOR UNIT COMMUNICATION ERROR SIZE 9K AND 12K CHART 5 -- OUTDOOR UNIT PROTECTS * CHART 6 -- INDOOR UNIT COMMUNICATION ERROR SIZE 18K AND 24K CHART 7 -- UNIT NOT RUNNING, NO DIAGNOSTIC CODE CHART 8 -- UNIT NOT RUNNING OPTIMALLY CHART 9 -- UNIT NOT RUNNING OPTIMALLY (HP IN HEATING)* CHART 10 -- COMPRESSOR CHART 11 -- OUTDOOR MOTOR CHART 12 -- REVERSING VALVE CHART 13 -- RECEIVER BOARD APPENDIX 38/40MVC, MVQ A 1 -- 5 3 M V C 0 0 9 -- -- -- 1 / 5 3 M V C 0 1 2 -- -- -- 1 A 2 -- 5 3 M V Q 0 0 9 -- -- -- 1 / 5 3 M V Q 0 1 2 -- -- -- 1 A 3 -- 5 3 M V C 0 1 2 -- -- -- 3 38/40MVC, MVQ A 4 -- 5 3 M V Q 0 1 2 -- -- -- 3 A 5 -- 5 3 M V C 0 1 8 -- -- -- 3 A6 -- Characteristics of Temperature Sensor A7 -- Fuse Chart A8 -- Indoor Unit Diagnostic Guides 9K & 12K Units 18K & 24K Units Fig. 34 LED Display Panel