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Functions and control
15
When all the ranges alternate, there is ±1
difference.
7.1.5 Heating mode:
(cooling only have no the mode)
*Temperature control range : 16
—30
*Temperature control precision: 1
*Control Character:
When Tr Ts, compressor, four-ways valve and outdoor fan motor is on, indoor fan motor runs as in cold blast
mode, and 4
of compensation is added after compressor is started.
When Tr
Ts+5
, compressor is off, and the indoor fan motor runs as in warm blast mode.
When Tr Ts+5
, compressor, four-ways valve and outdoor fan motor is on, and the indoor fan motor runs as in
the mode of avoiding cold blast.
*Control of indoor fan motor:
Manual operation: The wind speed can be set to high, medium, low or automatic as required.
Automatic operation: When Tr Ts, the wind speed is high;
When Ts Tr Ts+2
, the wind speed is medium.
When Ts+2
Tr, the wind speed is low.
*Control of air door: setting the position of air door as required.
*Compressor control
The compressor can’t be controlled by temperature sensor in 2 minutes after start up and
also can’t be started again at least 3 minutes later after shut down. There are 3-minute protection with power on for the
first time (over 3 minutes with power off). The compressor must be started again 3 minutes later after shut down.
*Avoiding electrical shock: outlet air is available 2 seconds later after start up.
*Timer on, Timer off and sleep control are available.
*Control of 4-way valve: When the unit is started for the first time, the 4-way valve starts running 10 seconds earlier
than compressor does. After compressor stops running, the 4-way valve continues running for 2 minutes and then
stops. If changing the unit from heating to cooling, the 4-way valve is shut off 2 minutes later and compressor is started
3 minutes later
.
7.1.5.1 Cold draft prevention:
7.1.5.1.1 Compressor is interrupted during the defrosting operation and continues to run after defrosting is
completed. When the indoor exchanging temperature is below 23
, the indoor fan motor is off. When the indoor
exchanging temperature is above 23
, the indoor fan motor is running at weak speed.
7.1.5.1.2 If the temperature of coil pipe can’t be above 38
4 minutes later after start up, fan motor is running at
the preset wind speed.
7.1.5.1.3 If the temperature of coil pipe is above 38
4 minutes later after start up, fan motor is running at the
preset wind speed.
7.1.5.1.4 If coil pipe descends to the temp. lower than 38
from 38
. fan motor is running at the preset wind
speed.
*Warm blast: If the temperature sensor is off. Compressor stops running. If the temperature of coil pipe is above
Ts-1
Ts
Ts+2
Ts+2
State3
State2
State1