CF-21
DUAL, TRIPLE, POKER DC Inverter : 5. Control Functions
Multi Liberty
DC Inverter
5.10 Automatic defrosting (during operation in Heating mode)
5.10.1 Conditions for start of automatic defrosting
Automatic defrosting starts when Outdoor Unit’s heat exchanger temperature (T4) has been lower than -2°C for
more than 40 minutes.
5.10.2 Conditions for end of automatic defrosting
Defrosting procedure ends, and normal operation in Heating mode is restored, when at least one of the following
conditions occurs:
a. Defrosting has already lasted for 10 minutes.
b. Heat exchanger’s temperature (T4) has reached a value of at least 15°C.
5.10.3 Operation of main components during defrosting
a. Compressor is operating.
b. 4-way valve switches over to OFF (position for operation in Cooling mode).
c. Outdoor Unit’s fan is stopped (OFF).
d. Fan operation on every Indoor Unit is controlled when anticold air drafts prevention control is active, as it has
previously described.
5.11 Operation in Auto mode (“AUTO”)
5.11.1 Concerning Auto mode, control electronics automatically selects the most suitable operation mode,
by choosing among “COOL”, “HEAT” or “FAN” according to the difference between temperature (T1) inside
the room and temperature (Ts) set by the User, as it is shown in the following Tables.
5.11.2 Indoor fan will run according to “AUTO” setting, relevant to operation mode selected by control
electronics, as it has already been described previously.
5.11.3 Air outlet motorized flaps will be controlled according to operation mode selected by control
electronics.
5.9.4 Indoor heat exchanger’s overheating prevention control (thermostatic OFF) in Heating mode.
For HFIU X Models, during thermostatic OFF in Heating mode, indoor fan will run at “Low” speed to prevent
overheating of Indoor Unit’s heat exchanger.
Temperature differential |T1 - Ts|
Operation mode
Cooling
Fan
|T1- Ts| > 2°C
-1°C ≤ |T1 - Ts| ≤ 2°C
Heating
|T1 - Ts| < -1°C
HKEU X Models