Haier AW09EH2VHD, Service Manual

Page: 25 / 70

SEQUENCE of OPERATION PAGE 25
52°F // //
48°F // //
43°F
Decreasing slowly
Decreasing rapidly
Stop
Keeping the frequency
Increasing slowly
32°F
Tpg1=37°F
Tpg2=41°F
Tpg3=45°F
Tpg4=48°F
3. Compressor Ov O er-current Protection
If the current draw of the compressor at start-up is greater
than the values listed on the chart below for
ff approximately 3
seconds, the compressor will stop. After 3 minutes the
compressor will restart. If the over-current condition occurs
3 times in 20 minutes, the system will lock-out, and a code
will be indicated at the outdoor unit. It will be necessary to
remove power to the system to reset the lock-out condi-
tion.
12A
10A
16A
15A
4. Anti-freeze Protection of the Indoor Coil
The temperature sensed by the coil sensor is used to dete-
rmine at what speed the compressor is to run to avoid the
coil temperature being too cold.
Tpg_indoor: indoor unit pipe sensor tempe
T T rature
When Min(Tpg_indoor , TpgTs)/2) < Tpg1, the freq-
uency of the compressor decreases at the rate of 1HZ / 1
When Tpg_indoor begins T T to rise again, and T T T
Tpg3, the frequency of T T the
compressor does not change.
When Tpg3 < T T
frequency of the compressor increases at the rate of 1HZ / 10
second
Example: if 32°F sust-
ains for ains f ains f 2 minutes, the outdoorunit will stop and indicate an
underload malfunction code at the outdoor unit. The com-
pressor stops for a minimum of 3 minutes. When Min(Tpg_
indoor , TpgTs)/2)>Tpg4, the compressor will
restart
5. Base Pan Heater
To keep condensate water from freezing inside the cabinet,
a base pan heater is installed at the factory. Refer to the
chart below for the operating parameters.
Ts: outdoor unit Suction Line sensor temperature
second.
When Min(Tpg_indoor , TpgTs)/2) < Tpg2, the freq-
uency of the compressor decreases at the rate of 1HZ / 10
Min(Tpg_i-
ndoor , TpgTs)/2)
Min(Tpg_indoor , TpgTs)/2) <Tpg4, the
second.
Min(Tpg_indoor , TpgTs)/2)
Current Overload Prodection
Outdoor Temperature Pan Heater
37 /3 OFF
28 /-2 to 34 /1 OFF 20min ON 10min
10 /-12 to 25 /-4 OFF 15min ON 15min
10 /-12 ON
Pan Heater Logic
Holds Decrease
Decrease Over-current
Model
value 1Hz/10s
1Hz/s point
09K 8A 9A 10A
12A
12K 13A 14A 15A
16A
18K 15A 16A 17A
18A