31
Technical Information
Service Manual
Outdoor Units
1. Input Parameter Compensation and Calibration
(1) Check the ambient temperature compensation function Indoor ambient temperature compensation function.
a. In cooling mode, the indoor ambient temperature participating in computing control = (T
indoor ambient temperature
–
⊿
T
cooling indoor ambient temperature
compensation
)
b. In heating mode, the indoor ambient temperature participating in computing control= (T
indoor ambient temperature
–
⊿
T
heating indoor ambient temperature
compensation
)
(2) Check effective judgment controls of parameters
Effective judgment function of the outdoor exhaust temperature thermo-bulb When conditions a and b are satisfied, the outdoor exhaust
temperature thermo-bulb is judged not to be connected into place, the mainboard of outer units will display failure of the outdoor exhaust
temperature thermo-bulb (not connected into place), stop the machine for repairing, and resume the machine by remote controls of ON/
OFF.
a. Judgment of exhaust detection temperature change:
After the compressor starts up and runs for 10 minutes, if the compressor frequency f ≥ 40Hz, and the rising value Texhaust (T
exhaust (after start-
up for 10 minutes)
- T
exhaust (before start-up)
) <35.6ºF , the outdoor exhaust temperature thermo-bulb can be judged not to be connected into place (judging
once when the power is on the first time).
b. Comparative judgment of exhaust detection temperature and condenser detection temperature (T
pipe temperature
= T
outdoor pipe temperature in cooling
mode
, T
pipe temperature
= T
indoor pipe temperature in heating mode
): After the compressor starts up and runs for 10 minutes, if the compressor frequency f ≥
40Hz, and T
pipe temperature
≥(T
37.4
), the outdoor exhaust temperature thermobulb can be judged not to be connected into place (judging
once when power is on the first time).
2. Basic Functions
(1) Cooling Mode
1. Conditions and processes of cooling operation:
(1) If the compressor is shut down, and [Tsetup – (T
indoor ambient temperature
–
⊿
T
cooling indoor ambient temperature compensation)
] ≤ 32.9ºF , start up the
machine for cooling, the cooling operation will start;
(2) During operations of cooling, if 32ºF ≤ [Tsetup – (T
indoor ambient temperature
–
⊿
T
cooling indoor ambient temperature compensation)
] < 35.6ºF , the cooling
operation will be still running;
(3) During operations of cooling, if 35.6ºF ≤ [Tsetup – (T
indoor ambient temperature
–
⊿
T
cooling indoor ambient temperature compensation)
], the cooling operation
will stop after reaching the temperature point.
2. Temperature setting range
(1) If T
outdoor ambient temperature
≥ [T
low-temperature cooling temperature
], the temperature can be set at: 60.8~86ºF (Cooling at room temperature);
(2) If T
outdoor ambient temperature
< [T
low-temperature cooling temperature
], the temperature can be set at: 77~86ºF (Cooling at low temperature), that is, the
minimum setting temperature for outer units judgment is 77ºF .
(2) Dehumidifying Mode
1. Conditions and processes of dehumidifying operations: Same as the cooling mode;
2. The temperature setting range is: 60.8~86ºF;
(3) Air-supplying Mode
1. The compressor, outdoor fans and four-way valves are switched off;
2. The temperature setting range is: 60.8~86ºF.
(4) Heating Mode
1. Conditions and processes of heating operations: (Tindoor ambient temperature is the actual detection temperature of indoor environment
thermo-bulb, Theating indoor ambient temperature compensation is the indoor ambient temperature compensation during heating
operations)
(1) If the compressor is shut down, and [(T
indoor ambient temperature
–
⊿
T
heating indoor ambient temperature compensation
) –T
setup
] ≤ 32.9ºF , start the machine
to enter into heating operations for heating;
(2) During operations of heating, if 32ºF ≤ [(T
indoor ambient temperature
–
⊿
T
heating indoor ambient temperature compensation
) –T
setup
] < 35.6ºF , the heating
operation will be still running;
(3) During operations of heating, if 35.6ºF ≤ [(T
indoor ambient temperature
–
⊿
T
heating indoor ambient temperature compensation
) –T
setup
], the heating operation
will stop after reaching the temperature point.
2. The temperature setting range in this mode is: 60.8~86ºF .
