Defrost Operation; Defrosting Program Entry Conditions; Conditions Used To Determination If Frost Has Formed; Defrost Actions - Haier AW09ES2VHB Service Manual

The suction line temperature sensor provides the tempera-
ture sensed at the incoming suction line pipe.
The compressor discharge sensor provides the temperature
sensed at the discharge pipe of the compressor.
To stop dry mode, press the power button to turn the system
off, or change to another mode.

Defrost Operation

Defrosting Program Entry Conditions

Condition 1: For the first time to power on the unit , the
compressor should run for 30 min accumulatively and run
continuously for 1 min . When meeting the frosting condition,
the defrosting is allowed.
Condition 2: After the first defrosting , the compressor with
heating mode should run for 30 min accumulatively and run
continuously for 1 min. and the time interval between de-
frosting cycle is more than 45 min. When meeting the frosting
condition, the defrosting is allowed.

Conditions Used to Determination if Frost has Formed

Under the running state of the compressor , by detecting
defrost sensor Te and outdoor ambient temperature sen-
sor Tao, it can satisfy any of the following conditions for 2
minutes continuously and is considered to meet the frosting
conditions
Condition 1: Let Tes(condensation temperature) =
C×Tao－α, When Tao < 0 32
then C=0.6 , α is set to a constant = 5.
Condition 2: Meet condition 1, and ΔT1-T1≥35.6
defined as Δ T1's minimum value, Δ T1 = T(outdoor ambient
temperature )-T (outdoor coil temperature).

Defrost Actions

• When C×Tao－α≥23 F, then Te≤23
O
cycle is 45min(Benchmark defrost cycle).
• When 14 O F ≤C×Tao－α<23
cycle is 45min(Benchmark defrost cycle).
• When 8.6 F < C×Tao－α ≤14
O
cycle is 65min (Def1 =65min-Benchmark defrost cycle ).
• When 5 F ≤C×Tao－α ≤ 8.6
O
cycle is 65min (Def1 =65min-Benchmark defrost cycle ).
• When C×Tao－α<5 F, then Te≤ 5
O
75min (Def2 =75min-Benchmark defrost cycle ).
• When defrosting begins, the compressor stops for 1min
first and outdoor fan runs at a high speed, after 50s, the
4-way off and then after 55s , the outdoor fan stops.
• The compressor start after 1min, the compressor run-
ning for 60s at defrosting frequency 38Hz and then running
for 60s defrosting frequency 58Hz and running for 60s at
defrosting frequency 88Hz , the final run is 88Hz.
• During the defrosting period, the mechanical and electrical
PAGE 26
F then C=0.8 , when Tao≥32
O
O F, T1 is
F and the defrost
O
O F , then Te≤Tes and defrost
F , then Te≤Tes and defrost
O
F, then Te≤Tes and defrost
O
F and defrost cycle is
O
SEQUENCE OF OPERATION
current of the compressor and the air vent of the com-
pressor are effectively protected.
• After entering defrosting, the minimum running time must
be guaranteed 2 minutes before exiting defrosting.

Defrosting Exit Conditions

When any of the following conditions are met, the defrosting
operation returns to the heating operation
• The temperature of the outdoor coil exceeds 44.6
seconds continuously
• The temperature of the outdoor coil exceeds 53.6
seconds continuously
• Continuous 11 minutes for defrosting operation
• During defrosting, valve opening remains unchanged at
200, and the opening of defrosting starting valve is con-
trolled according to starting oil return

TTC High Temperature Protection

The compressor discharge pipe sensor (exhaust temp)
senses the temperature of the refrigerant exiting the com-
pressor. The sensed temperature received from the sensor
by the control circuitry will cause the compressor frequency
to increase or decrease. (see chart below). If a temperature
of >= 230°F is sensed for 20 seconds, an exhaust overheating
protection error code will be indicated at the outdoor unit.
TTC (°F)
230
°F
F
O
212
°F
209
°F
199
°F
194
°F

Protection Functions

Abnormal stop
Decreasing the frequency rapidly (1HZ/1second)
Decreasing the frequency slowly (1HZ/10 seconds)
The frequency doesn't change
Increasing the frequency (1HZ/10 seconds)
Increasing the frequency (1HZ/1second)
F for 60
O
F for 20
O