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SXIH-SVX01C-EN
Maintenance
Troubleshooting
Use the following steps and procedures to help correct these common problems.
WARNING
Hazardous Voltage!
Disconnect all electric power, including remote disconnects before servicing. Follow proper
lockout/tagout procedures to ensure the power can not be inadvertently energized. Failure to
disconnect power before servicing could result in death or serious injury.
Problem
Remedy
The entire unit does not operate.
Possible cause
1. Power interruption
1. Check for blown fuses or tripped circuit breakers. Replace or reset if
necessary.
2. Thermostat not operating
2. Setting may be too high; check unit and reset. Thermostat may be
out of calibration or otherwise defective; replace.
3. Electrical panel
a. 24-volt transformer defective
b. loose wire
3. Correct as required.
Problem
Remedy
Fan runs but compressor does not start.
Possible cause
1. Low voltage
1. Check power supply for voltage outside the acceptable voltage range.
2. Remote thermostat
2. Check the control unit for loose wires. Firm any loose connections.
3. Compressor contactor open or burned
3. Replace.
4. High pressure control cutting out unit
4. Check for loose wire connection, broken or burned contacts. If defective,
replace.
5. Refrigerant leak - no gas
5. Locate leak and repair. Recharge unit.
6. Loose or defective wires.
6. Tug on wires to see if they will separate from connections. Replace
terminals if necessary.
7. Compressor shorted, open or burned
7. Check for shorts, opens, and grounded. Remove and replace
compressor.
8. Defective compressor
8. Remove and replace.
Problem
Remedy
Unit held off by safety.
Possible cause
1. Unit cutout on high pressure control, set at
395 psig for SCIH or 609 psig for SCIJ
1. Verify the airflow is uninterrupted. Also, verify that the low
ambient damper is set properly, allowing condensing
temperatures of 90–135°F. Reset high pressure switch to start.
2. Refrigerant leak
2. See if unit is low on refrigerant charge. Repair leak and recharge
unit.
3. Air restriction, dirty coils
3. Verify if the air filter is dirty or has an airflow restriction, and
correct problem.
4. Partial restriction in refrigerant system
4. Locate restriction by inspecting refrigerant lines for temperature
changes. Remove restriction, evacuate, and recharge.
5. High pressure control
5. Replace, if defective.
6. TXV power element charge loss
6. Evacuate, replace element, recharge.
7. Loose connection in electrical unit
7. Trace and firm up connection.
Problem
Remedy
Noisy operation.
Possible cause
1. Copper tubing vibrating
1. Adjust tubes by bending slightly to firm position
without touching other unit parts.
2. Machine vibrating out of level
2. Level unit base. Fully support base.
3. Loose cabinet or internal component
3. Check and tighten loose screws.
4. Loose fan wheel
4. Tighten screws on fan wheel shaft.
5. Blower wheel hitting shroud
5. Adjust wheel position on motor shaft
6. Blower motor bearing defective
6. Replace fan motor.
7. Blower bearing defective
7. Replace fan bearing.
maintenance procedure
