Carrier air troubleshooting

Is your Carrier air conditioner making unusual noise, not cooling or not heating? Are there any other strange symptoms? The tips provided in the table below will help you with the most common problems that may occur with an air conditioning system. In many cases troubleshooting home appliances is possible even for do-it-yourselfers without much experience.

Carrier 38BK-009 air troubleshooting

TroubleCheck PointsAction
Unit does not operate• Check that the power cord is plugged into the wall outlet.Insert the power cord into the wall outlet
• Has the circuit breaker tripped or the fuse blown?Reset the circuit breaker or replace the fuse with the specified replacement fuse.
• Has there been a power failure?Flestart operation when power is resumed.
• If the "UNIT ON" lamp flashes on and off?Call your service representative.
• Is the voltage too low?Confirm the available voltage.
Cooling is abnormally low.• Is the filter blocked with dust?Clean the air filter.
• Has the temperature been set property?Check and reset it if necessary.
• Are the windows and doors opened?Close the windows and doors.
• Is anything obstructing the outdoor unit?Flemove the obstruction.
• Is the fan speed too low?Change the fan speed selection.
• Is the operation mode FAN or AUTO?Change to cooling operation or reset temperature.
Heating is abnormally low.• Is the fitter blocked with dust?Clean the air filter.
• Has the temperature been set too low?Check and reset it if necessary.
• Are the windows or doors opened?Close the windows and doors.
• Is anything obstructing the outdoor unit?Remove the obstruction.
Unit stops during ' operation.• Has the OFF timer operated?Switch OFF timer function.
• Has the room temperature reached the set temperature?Normal operation.
Air cleaning does not operate.• On the indoor unit display, is the air cleaning lamp turned off and the checking lamp turned on?Press the RESET button.
Air cleaning lamp is turned on after a minute. If not, call service representative.

Carrier WEATHERMAKER 4850AJ air troubleshooting

PROBLEMSOLUTION
COMPRESSOR DOES NOT RUN Active AlarmCheck active alarms using local display.
Contactor ODen
1. Power off.1. Restore power.
2. Fuses blown in field power circuit.2. After finding cause and correcting, replace with correct size fuse.
3. No control power.3. Check secondary fuse(s); replace with correct type and size. Replace transformer if primary windings receiving power.
4. Compressor circuit breaker tripped.4. Check for excessive compressor current draw. Reset breaker; replace if defective.
5. Safety device lockout circuit active.5. Reset lockout circuit at circuit breaker.
6. High-pressure switch open.6. Check for refrigerant overcharge, obstruction of outdoor airflow, air in system or whether compressor discharge valve is fully open. Be sure outdoor fans are operating correctly.
7. Loose electrical connections.7. Tighten all connections.
Contactor Closed
1. Compressor leads loose.1. Check connections.
2. Motor windings open.
3. Single phasing.3. Check for blown fuse. Check for loose connection at compressor terminal.
4. ASTP activated (48/50A2,A3,A4,A5 only)4. Allow 30 to 120 minutes for cool down.
COMPRESSOR STOPS ON HIGH PRESSURE Outdoor Fan On
1. High-pressure switch faulty.1. Replace switch.
2. Airflow restricted.2. Remove obstruction.
3. Air recirculating.3. Clear airflow area.
4. Noncondensables in system.4. Purge and recharge as required.
5. Refrigerant overcharge.5. Purge as required.
6. Line voltage incorrect.6. Consult power company.
7. Refrigerant system restrictions.7. Check or replace filter drier, expansion valve, etc. Check that compressor discharge valve is fully open.
8. Fan running in reverse direction.8. Correct wiring.
Outdoor Fan Off
1. Fan slips on shaft.1. Tighten fan hub setscrews.
2. Motor not running.2. Check power and capacitor.
3. Motor overload open.3. Check overload rating. Check for fan blade obstruction.
4. Motor burned out.4. Replace motor.
COMPRESSOR CYCLES ON LOW PRESSURE Indoor-Air Fan Runnina
1. Filter drier plugged.1. Replace filter drier.
2. Expansion valve power head defective.2. Replace power head.
3. Low refrigerant charge.3. Add charge.
4. Faulty pressure transducer.4. Check that pressure transducer is connected and secured to suc- tion line. If still not functioning, replace transducer.
Airflow Restricted
1. Coil iced up.1. Check refrigerant charge.
2. Coil dirty.2. Clean coil fins.
3. Air filters dirty.3. Clean or replace filters.
4. Dampers closed.4. Check damper operation and position.
Indoor-Air Fan StoDDed
1. Electrical connections loose.1. Tighten all connections.
2. Fan relay defective.2. Replace relay.
3. Motor overload open.3. Power supply.
4. Motor defective.4. Replace motor.
5. Fan belt broken or slipping.5. Replace or tighten belt.
COMPRESSOR RUNNING BUT COOLING INSUFFICIENT
Suction Btessur.e.Low
1. Refrigerant charge low.1. Add refrigerant.
2. Head pressure low.2. Check refrigerant charge.
3. Air filters dirty.3. Clean or replace filters.
4. Expansion valve power head defective.4. Replace power head.
5. Indoor coil partially iced.5. Check low-pressure setting.
6. Indoor airflow restricted.6. Remove obstruction.
UNIT OPERATES TOO LONG OR CONTINUOUSLY
1. Low refrigerant charge.1. Add refrigerant
2. Control contacts fused.2. Replace control.
3. Air in system.3. Purge and evacuate system.
4. Partially plugged expansion valve or filter drier.4. Clean or replace.
SYSTEM IS NOISY
1. Piping vibration.1. Support piping as required.
2. Compressor noisy.2. Replace compressor.
COMPRESSOR LOSES OIL
1. Leak in system.1. Repair leak.
2. Crankcase heaters not energized during shutdown.2. Check wiring and relays. Check heater and replace if defective.
HOT LIQUID LINE
1. Shortage of refrigerant due to leak.1. Repair leak and recharge.
2. Expansion valve opens too wide.2. Adjust expansion valve.
FROSTED LIQUID LINE Restricted filter drier.
INDOOR FAN CONTACTOR OPENRemove restriction or replace.
1. Power off.1. Restore power.
2. Fuses blown in field power circuit.2. After finding cause and correcting, replace with correct fuses.
3. No control power.3. Check secondary fuses. Replace with correct type and size. Replace transformer if primary windings are receiving power.
INDOOR FAN CONTACTOR CLOSED
1. VFD overload function tripped.
2. Motor leads loose.2. Check connections at motor lead junction box.
3. Motor windings open.3. Check motor windings.
4. Single phasing.4. Check for blown fuse. Check for loose connections at motor junction box.
5. Belts broken or thrown.5. Check belts. Replace as complete set if necessary.
6. Circuit breaker tripped.6. Check for excessive current draw. Reset breaker. Replace if defective.

Carrier Superia Plus K+ Series air troubleshooting

MalfunctionsCauseWhat should be done?
Unit does not startPower cutWait for power to be restored.
Unit may have become Unplugged.Check that plug is securely in wall receptacle.
Fuse may have blown.Replace the fuse.
Battery in Remote controller may have been exhausted.Replace the battery.
The time you have set with timer is incorrect.Wait or cancel timer setting.
Unit not cooling or heating (Cooling/ heating models only) room very well while air flowing out from the air conditionerInappropriate temperature setting.Set temperature correctly
Air filter is blocked.Clean the air filter.
Doors or Windows are open.Close the doors or windows.
Air inlet or outlet of indoor or outdoor unit has been blocked.Clear obstructions away first, then restart the unit.
Compressor 3 or 4 minutes protection has been activated.Wait.

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