Troubleshooting - Carrier 38MURA Owner's Manual

40MUAA: Owner's Manual

TROUBLESHOOTING

WARNING
SAFETY PRECAUTIONS
If any of the following conditions occur, turn off the unit
immediately:
The power cord is damaged or abnormally warm.
You smell a burning odor.
The unit emits loud or abnormal sounds.
A power fuse blows or the circuit breaker frequently trips.
Water or other objects fall into or out of the unit.
DO NOT attempt to fix these issues yourself. Contact an
authorized service provider immediately!
The issues in Table 2 are not malfunctions and in most cased do not require repairs.
Issue
Unit does not turn on when user
presses ON/OFF
The unit changes from COOL/
HEAT mode to FAN mode
The indoor unit emits white
mist
Both the indoor and outdoor
units emit white mist
The indoor unit makes noises
Both the indoor unit and
outdoor unit make noises
The outdoor unit makes noises
Dust emits from either the
indoor or outdoor unit
The unit emits a bad odor
The outdoor unit fan does not
operate
NOTE: If an issue persists, contact a local dealer or your nearest customer service center. Provide them with a detailed
description of the unit's malfunction as well as the unit's model number.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Table 2 — Common Issues
The unit has a 3-minute protection feature that prevents the unit from overloading. The unit cannot be restarted
within three minutes after being turned off.
COOLING and HEATING models: If the Operation light and PRE-DEF (Pre-heating/ Defrost) indicators are
illuminated, the outdoor temperature is too cold and the unit's anti-cold wind is activated to defrost the unit.
In the COOLING-only models: If the "Fan Only" indicator is illuminated, the outdoor temperature is too cold and
the unit's anti-freeze protection activates to defrost the unit.
The unit may change its setting to prevent frost from forming on the unit. Once the temperature increases, the unit
starts operating in the previously selected mode again.
The set temperature has been reached, at which point the unit turns off the compressor. The unit continues
operating when the temperature fluctuates again.
In humid regions, a large temperature difference between the room's air and the conditioned air can cause white
mist.
When the unit restarts in the HEAT mode (after defrosting), white mist may be emit due to moisture generated
from the defrosting process.
A squeaking sound is heard when the system is OFF or in the COOL mode. The noise is also heard when the drain
pump (optional) is operating.
A squeaking sound may occur after running the unit in the HEAT mode due to expansion and contraction of the
unit's plastic parts.
Low hissing sound during operation: This is normal and is caused by refrigerant gas flowing through both the
indoor and outdoor units.
Low hissing sound when the system starts, has just stopped running, or is defrosting. This noise is normal and is
caused by the refrigerant gas stopping or changing direction.
Squeaking sound: Normal expansion and contraction of plastic and metal parts caused by temperature changes
during operation can cause squeaking noises.
The unit makes different sounds based on the current operating mode.
The unit may accumulate dust after extended periods of non-use. Dust can emit when the unit is turned on. This can
be mitigated by covering the unit during long periods of inactivity.
The unit may absorb odors from the environment (such as furniture, cooking, cigarettes, etc.) which will emit
during operations.
The unit's filters have become moldy and should be cleaned.
During operation, the fan speed is controlled to optimize product operation.
Possible Causes
6