Haier N Series Service Manual page 20

When the outdoor unit is shut down, the valve is opened completely for 2 minutes, and then
begin initialization.
The scope of refrigerationg valve
The scope of heating valve
The valves are adjusted according to the degree of superheat
7.1.2 Four way control
For the details of defrosting four-way valve control, see the defrosting process.
Four way working in other ways:
Under the mode of heating, open the four-way valve, when the compressor is not started or
changed to non-heating mode, make sure the compressor is stoped for 2 minutes, and then
close the four-way valve.
7.1.3 Protection function
7.1.3.1 TTC high temperature-preventing
Once the machine is started, it can run TTC overheating protection of air-blowing, but air-blowing
sensor malfunction must alarm after 4 minutes during which the compressor is started (during the
course of self-detection, there's no such limitation)
Sensor detection methods: 100 times (one cycle of procedure run is one time, and about 5ms,
detection method for each time: continuously sampling for 8 times, then order them and take the
mean value of the middle 2 values), take the mean value.
TTC
110
100
98
93
90
TTC>=110
the indoor, others don't last.
TC high temperature-preventing control of the indoor heating unit
7.1.3.2
Tpg_indoor is the highest value of the effective indoor unit (start it and it is in accord with the
running state).
The indoor heat exchanger sensor tests the temperature of the indoor heat exchanger. If the
temperature is higher than 55 , decrease the rotate speed of the compressor and do the high
temperature-preventing protection of the indoor heat exchanger; if the temperature of the indoor
heat exchanger is lower than 47 , recover to the normal control.
Abnormal stop
Decreasing the frequency rapidly 1HZ/second
Decreasing the frequency slowly (1HZ/10seconds)
The frequency doesn't change.
lasts for 20 seconds. Overheating protection of air-blowing, alarm malfunction to
90-----480 steps
80-----480 steps
protection
Increasing the frequency (1HZ/10second)
Increasing the frequency 1HZ/1second
18
Functions and control
SHa SHa.
Domestic air conditioner