17
Technical Information
Service Manual
6.2 Brief Description of Modes and Functions
(1) Cooling Mode
①
Working conditions and process of cooling
When Tamb.≥Tpreset, the unit will enter cooling operation, in which case the indoor fan, the outdoor fan and the compressor will work and the
indoor fan will run at preset speed.
When Tamb.≤Tpreset -3.6°F, the compressor will stop, the outdoor fan will stop with a time lag of 30s, and the indoor fan will run at preset
speed.
When Tpreset -3.6°F< Tamb.< Tpreset , the unit will remain at its previous state.
Under this mode, the four-way valve will be de-energized and temperature can be set within a range from 61~to 86°F.
If the compressor is shut down for some reason, the indoor fan and the swing device will operate at original state.
②
Protection
◆
Antifreeze protection
Under cooling and dehumidifying mode, 6 minutes after the compressor is started:
If T evap≤35.6°F, the compressor will operate at reduced frequency.
If T evap≤30.2°F is detected for durative 3 minutes, the compressor will stop, and after 30 seconds, the outdoor fan will stop; and under
cooling mode, the indoor fan and the swing motor will remain at the original state.
If T evap. ≥42.8°F and the compressor has remained at OFF for at least 3 minutes, the compressor will resume its original operation state.
◆
Total current up and frequency down protection
When total current Itotal≤5.5A, increase frequency is allowed; when total current Itotal≥6A, increasing frequency is prohibited; when tota
current Itotal≥7A, the unit operates by decreasing frequency. When total current Itotal≥9A, the compressor stops operation, and indoor fan will
stop operation after 30s.
(2) Dehumidifying Mode
①
Working conditions and process of dehumidifying
If Tamb>Tpreset, the unit will enter cooling and dehumidifying mode, in which case the compressor and the outdoor fan will operate and the
indoor fan will run at low speed.
If Tpreset -3.6°F≤Tamb≤Tpreset, the compressor remains at its original operation state.
If Tamb.< Tpreset -3.6°F, the compressor will stop, the outdoor fan will stop with a time lag of 30s, and the indoor fan will operate at low speed.
②
Protection
Protection is the same as that under the cooling mode.
(3) Heating Mode
①
Working conditions and process of heating
If Tamb.≤T3.6°F, the unit enters heating mode, in which case the four-way valve, the compressor and the outdoor fan will operate
simultaneously, and the indoor fan will run at preset speed in the condition of preset cold air prevention.
If T amb.≥T9°F, the compressor will stop, the outdoor fan will stop with a time lag of 30s, and the indoor fan will stop after 60-second
blow at low speed.
If T3.6°F<T amb.< T9°F, the unit will maintain its original operating status.
Under this mode, the four-way valve is energized and temperature can be set within a range of 61 ~ 86°F. The operating symbol, the heating
symbol and preset temperature are revealed on the display.
②
Condition and process of defrost
When duration of successive heating operation is more than 45 minutes, or accumulated heating time more than 90 minutes, and one of the
following conditions is reached, the unit will enter the defrost mode after 3 minutes.
a. When Toutdoor amb.≥41°F, Toutdoor tube≤28.4°F;
b. When 28.4°F≤Toutdoor amb.
<
41°F, Toutdoor tube≤21.2°F;
c. When 23°F≤Toutdoor amb.
<
28.4°F, Toutdoor tube≤14°F;
d. When 14°F≤Toutdoor amb.
<
23°F, Toutdoor tube≤(Toutdoor amb.-10.8)°F;
e. When Toutdoor amb.
<
14°F, Toutdoor tube≤(Toutdoor amb.-7.2)°F;
In this case, the compressor and indoor fan stop, while the outdoor fan and 4-way valve stop after 30s; after another 30s, the compressor
starts with the operation frequency of 70Hz. When the compressor has operated for 8min or Toutdoor tube≥50°F, the compressor stops and
the 4-way valve starts after 30s; after another 60s, the compressor and outdoor fan resumes operation,and the indoor fan operates according
to the condition of cold air prevention.
③
Protection
◆
Cold air prevention
The unit is started under heating mode (the compressor is ON):
①
In the case of T indoor amb. <75.2°F: if T tube≤104°F and the indoor fan is at stop state, the indoor fan will begin to run at low speed
with a time lag of 2 minutes. Within 2 minutes, if T tube>104°F, the indoor fan also will run at low speed; and after 1-minute operation at low
speed, the indoor fan will be converted to operation at preset speed. Within 1-minute low speed operation or 2-minute non-operation, if T
tube>107.6°F, the fan will run at present speed.
②
In the case of T indoor amb. ≥75.2°F: if T tube≤107.6°F, the indoor fan will run at low speed, and after one minute, the indoor fan will be
converted to preset speed. Within one-minute low speed operation, if T tube>107.6°F, the indoor fan will be converted to preset speed.
Note: T indoor amb. indicated in
①
and
②
refers to, under initially heating mode, the indoor ambient temperature before the command to start
the compressor is performed according to the program, or after the unit is withdrawn from defrost, the indoor ambient temperature before the
defrost symbol is cleared.
◆
Total current up and frequency down protection
When total current Itotal≤6A, increase frequency is allowed; when total current Itotal≥7A, increasing frequency is prohibited; when tota current
Itotal≥8A, the unit operates by decreasing frequency. When total current Itotal≥9A, the compressor stops operation, and indoor fan will stop
operation after 30s.
Содержание ACZCI4C4R12
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