Fedders GWH18MC-D3DNA1A/O, Service Manual

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26
Function and Control
(3) Protecting Treatments of Thermo-bulb:
1.When the thermo-bulb is detected to be short-circuited continuously for 30 seconds:
It is regarded that the temperature detected by the thermo-bulb is over-high (or unlimited), then the whole
machine will exert corresponding safety stops according to the over-high temperature sensed by the thermo-bulb,
and display corresponding temperature safety stops and faults of the thermo-bulb simultaneously.
2. When the thermo-bulb is detected in open circuit continuously for 30 seconds: stop the machine in protection,
directly display corresponding faults of the thermo-bulb.
4. Forced Running Function of the In
door
Units
(1) Enter into Forced Running Control
Within 5 minutes after power-up, press the Lights Off button on the remote controller continuously for three
times within 3 seconds to enter into the fluorine collecting mode, and display Fo, send the fluorine-collecting
mode for 25 minutes continuously, each load will be treated as cooling when starting the machine (set the air flow
as High, set the temperature as 16 ).
(2) Exit from the Forced Running Control
After receiving any remote signal, or signal of keys, the fluorine-collecting mode will exit, and operate in
accordance with the current orders set; or exit the fluorine-collecting mode after running for 25 minutes, and the
machine will be shut down automatically.
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 T
exhaust
(T
exhaust (after start-up for 10 minutes
) - T
exhaust (before start-up)
) < 2 , 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
exhaust
+ 3 ), the outdoor exhaust temperature thermo-bulb 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 [T
setup
– (T
indoor ambient temperature
– T
cooling indoor ambient temperature
compensation
)] ≤ 0.5 , start up the machine for cooling, the cooling operation will start;
(2) During operations of cooling, if 0 ≤ [T
setup
– (T
indoor ambient temperature
– T
cooling indoor ambient temperature
compensation
)] < 2 , the cooling operation will be still running;
(3) During operations of cooling, if 2 ≤ [T
setup
– (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: 16~30 (Cooling at
room temperature);
(2) If T
outdoor ambient temperature
< [T
low-temperature cooling temperature
], the temperature can be set at: 25~30 (Cooling at
low temperature), that is, the minimum setting temperature for outer units judgment is 25 .