Typical Operational Occurrences - Heat Controller SMA 09 Owner's Manual

Heat Controller, Inc.

Typical Operational Occurrences

The following events may occur during normal operation.
1. Protection of the air conditioner.
Compressor protection
• If the unit is stopped and then immediately restarted again, the compressor will not operate for about
3 minutes in order to protect the compressor.
Anti-cold air (heat pump models only)
• The unit is designed not to blow cold air in HEAT mode, when the indoor heat exchanger is in one of
the following three situations and the set temperature has not been reached.
A) When heating has just starting.
B) Defrosting is occurring
C) Low temperature heating is occurring
Defrosting (Cooling and heating models only)
• The indoor or outdoor fan stop running when defrosting (heat pump models only).
• Frost may accumulate on the outdoor unit during heat cycle when outdoor temperature is low and hu-
midity is high, resulting in lower heating efficiency of the air conditioner.
• During this condition, air conditioner will stop the heating operation and start defrosting automatically.
• Defrost time may vary from 4 to 10 minutes according to the outdoor temperature and the amount of
frost buildup on the outdoor unit.
2. Mist or steam are being emitted
• A white mist may emit from the indoor unit due to a large temperature difference between air inlet and
air outlet in COOL mode in an indoor environment that has a high relative humidity.
• A white mist may emit due to moisture generated from the defrosting process when the air conditioner
restarts in HEAT mode operation after defrosting.
3. Typical sounds
• You may hear a low hissing sound when the compressor is running or has just stopped running. This
sound is the sound of the refrigerant flowing or coming to a stop.
• You can also hear a low "squeak" sound when the compressor is running or has just stopped running.
This is caused by heat expansion and cold contraction of the plastic parts in the unit when the tempera-
ture is changing.
• A noise may be heard due to louver restoring its original position when power is first turned on.
• A sizzling sound may be heard occasionally when the unit is defrosting.
4. Dust is blown out from the indoor unit
• This is a normal condition when the air conditioner has not been used for a long time or during first use
of the unit and an accumulation of dust has formed on the unit's outlet. Cleaning dust off of the unit
before operation will prevent this.
5. A peculiar smell comes out from the indoor unit
• This is caused by the indoor unit giving off smells permeated from building material, from furniture, or
smoke. A burning smell could mean there is something wrong with the unit. Power off the unit and call
an authorized servicer.
6. Operating mode changes to FAN ONLY mode
• When the indoor temperature reaches the temperature set point on air conditioner, the compressor will
stop automatically, and the air conditioner mode changes to FAN only mode. The compressor will start
again when the indoor temperature rises above the set point in the COOL mode or falls below the set
point in the HEAT mode (heat pump only models).
OWNER'S MANUAL
8
SMA/SMH