Haier AW07LC2VHA Technical Overview Download

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OPERATIONS

PAGE 24

ENGLISH

10.2.6 Forced Defrost Operation

The system can be placed into a forced defrost cycle from the
wired controller. The system will remain in defrost until sensor
Te has sensed 53.6°F for at least 1 minute or until the defrost
cycle has reached 10 minutes total runtime.

A forced defrost cycle can be initiated with the compressor
off. The system will enter a 3 minute time delay prior to
energizing the compressor.

10.2.7 Defrosting Time Flowchart

10.2.7 Defrosting operation flow chart:

beginning

end

fixed frequency

indicated FQY 60s

defrosting FQY 80 Hz

（

）

60s

soft startup

compressor

0HZ

outdoor motor ON

send defrosting signal to indoor

Auto

OFF

4-way valve

OFF

15s

450-pulse

350-pulse(E)

all EEVs

auto open angle

all indoor motors ON

OFF

anti-cold air function

10.2.8 Frequency Control and Compressor Discharge Line
Temperature

If the temperature of the discharge line gets too high, and
the EEV adjustment cannot correct the problem, the ECU will
make frequency adjustment to the speed of the compressor
in an attempt to cool it down. The chart here shows the
adjustment steps versus the discharge line temperature.

10.2.8 Frequency Control when there is CT Over-current
Protection

10.2.8 Frequency control when compressor discharge temp.

（

）

is too high

Purpose: make compressor frequency control if the discharging temp. is too high, to lower the discharging
temp. efficiently and ensure the system can run normally.

Multi:

Dischar

gin

tem

Reduce FQY rapidly 2HZ/S

Reduce FQY rapidly 1HZ/S

Reduce FQY slowly 1HZ/10S

Remain FQY

Increase FQY slowly 1HZ/10S

If keeping for 10s, the unit stops, 3 minutes later, the unit can
re-startup. If in 60 minutesthe unit occurs alarm for 3 times, the
failure can be eliminated.

248

℉

239

℉

230

℉

221

℉

212

℉

203

℉

nde

g t

Keep for 5 seconds, stop to alarm, after 3-minute standby, the

unit will stop to alarm and the failure can be resumed after being
electrified again.
Reduce FQY rapidly 2HZ/S

Reduce FQY rapidly 1HZ/S

Reduce FQY slowly 1HZ/10S

Remain FQY

Increase FQY slowly 1HZ/10S

1.0 I

0.95I

0.93I

0.90I

0.88I

0.85I

Stop immediately, if abnormal stop 3 times in 1 hour, the

unit will stop and alarm.

Reduce FQY rapidly 2HZ/S

Reduce FQY rapidly 1HZ/S

Reduce FQY slowly 1HZ/10S

Remain FQY

Increase FQY slowly 1HZ/10S

unit can restartup. In 60 minutes it occurs 3 times continously,

10.2.8.

10.2.9.

When the input signal of pressure switch is low level: 0 for 1 minute, that shows high pressure

10.2.10.

(1) When compressor is running, if output signal of low pressure switch is low level: 0 for 1

(2) When compressor no running, if output signal of low pressure switch is low level: 0 for 30

156

℉

154

℉

151

℉

147

℉

144

℉

140

℉

code to indoor. Meanwhiel, by controling the max. condensating temp.Tc(cooling) or module temp. sensor(TmAVE),

please confirm as follow

10.2.9 High Pressure Protection

If abnormally high refrigerant circuit condensing pressure is
detected, the high pressure switch will open. The outdoor unit
will initiate an Error Code and stop compressor operation. If
the system pressure drops enough to re-close the switch the
system will re-start. If the failure occurs 3 times, the system
will lock out and display the appropriate Error Code.

High condensing temperature can also cause high pressure.
The ECU will monitor the temperature of the condensing coil
in both heating and cooling modes of operation. Frequency
adjustments will be made to the compressor speed in an
attempt to manage high pressure that can be caused by dirty
condensing coils and high heat loading. The chart below shows
the ECU frequency response at high condenser temperatures.
(Indoor Coil Heat Mode, Outdoor Coil Cool Mode)

nde

g t

Keep for 5 seconds, stop to alarm, after 3-minute standby, the

unit will stop to alarm and the failure can be resumed after being
electrified again.
Reduce FQY rapidly 2HZ/S

Reduce FQY rapidly 1HZ/S

Reduce FQY slowly 1HZ/10S

Remain FQY

Increase FQY slowly 1HZ/10S

1.0 I

0.95I

0.93I

0.90I

0.88I

0.85I

Stop immediately, if abnormal stop 3 times in 1 hour, the

unit will stop and alarm.

Reduce FQY rapidly 2HZ/S

Reduce FQY rapidly 1HZ/S

Reduce FQY slowly 1HZ/10S

Remain FQY

Increase FQY slowly 1HZ/10S

unit can restartup. In 60 minutes it occurs 3 times continously,

10.2.8.

10.2.9.

When the input signal of pressure switch is low level: 0 for 1 minute, that shows high pressure

10.2.10.

(1) When compressor is running, if output signal of low pressure switch is low level: 0 for 1

(2) When compressor no running, if output signal of low pressure switch is low level: 0 for 30

156

℉

154

℉

151

℉

147

℉

144

℉

140

℉

code to indoor. Meanwhiel, by controling the max. condensating temp.Tc(cooling) or module temp. sensor(TmAVE),

please confirm as follow

10.2.10 Low Pressure Protection

The system low pressure switch is normally closed. The
switch will open when the refrigerant pressure gets too low.
Typical causes are refrigerant leaks/undercharging and low
evaporator heat loading. The system will auto re-start if the
switch re-closes after opening. If the switch opens 3 times in
60 minutes of running, the system will display an error code.

The low pressure switch is checked even when the system
is off. This protects the compressor against operating with a
great loss of refrigerant when the system has been off for a
long time.

OUTDOOR UNIT TEMPERATURE SENSOR RESPONSES

Forced Defrost Operation