7
2.5 Heating
2.5.1 Indoor fan motor control
Fan speed
:
High,medium,low,auto.
If choosing “Auto” mode, then indoor fan motor chooses fan speed according to indoor
temperature and the set temperature.
2.5.2 Cool-airflow-prevention while heating
Avoid cool airflow
:
At the beginning of heating mode, if the temperature of indoor pipe coil is
lower than the prescribed value, and compressor stops or running time less than the
prescribed time
(
If exceeding the prescribed time,the unit will exist
cool-airflow-prevention.
),
the unit is in cool-airflow-prevention condition, then louver blades
can not swing and indoor fan motor stops. The PAUSE indicator lights during
cool-airflow-prevention period.
2.5.3 Heating capacity control
Calculating the difference value between the temperature detected by indoor pipe
temperature sensor and the prescribed indoor pipe value temperature to determine the
correction of frequency command signal, correct the frequency command signal currently
existing. When the indoor pipe temperature is higher than the prescribed indoor pipe value
temperature, the unit will decreases the rotary speed of compressor.
2.5.4 High-loaded control
Indoor pipe coil temperature sensor examines evaporator temperature, if temperature
exceeds the prescribed value, the frequency does not increase; if temperature exceeds
upper limit value, the rotary speed of compressor will be gradually decreased to avoid too
high heat load
;
if temperature is lower than the prescribed value, the frequency does not
decrease; if temperature is lower than lower limit value, unit will exist high-loaded control
and enters normal operation.
2.5.5 Over current control
If the value of input current detected by outdoor current sensor is higher than the prescribed
value, the rotary speed of compressor will be decreased and controlled in order to keep the
current value not higher than the upper limit value
;
compressor will come to normal
operation when the current value drops to the lower limit value
;
If current value is higher than
the prescribed value, compressor stops.
2.5.6 Defrosting control
2.5.6.1 Defrosting test
When machine is in heating mode, it controls defrosting through defrosting sensor (Te)
detecting the frost level of heat exchanger.
2.5.6.1.1The first conditions of entering defrosting:
2.5.6.1.1.1 The prerequisite of defrosting: heating compressor is running for 10 minutes and
45 minutes in total ( general defrosting)/ 90 minutes
【(
low temperature defrosting
:
outer
environmental temperature is under
-
6
℃】;