Haier N Series Service Manual page 20

7.1.5 Protection function
7.1.5.1 TTC high temperature-preventing protection
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.
7.1.5.2 TC high temperature-preventing control of the indoor heating unit
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.
TC
Fgh_t1 2
59
Fgh_t2 2
Fgh_t3 2
Fgh_t4 2
Fgh_t5 2
Normal
Abnormal stop
Decreasing the frequency rapidly 1HZ/second
lasts for 20 seconds. Overheating protection of air-blowing, alarm malfunction to
Decreasing the frequency slowly (1HZ/10seconds)
The frequency doesn't change.
Increasing the frequency (1HZ/10second)
Increasing the frequency 1HZ/1second
The compressor stops
N Decreasing the frequency rapidly
P Decreasing the frequency slowly
Q Prohibiting increasing the frequency
R Increasing slowly
18
Functions and Control
Fgh_t1 65
Fgh_t3 55
Fgh_t4 51
Fgh_t5 47
Domestic air conditioner
Fgh_t2