GE ASYW09CRAWA Service Manual Download

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SEQUENCE of OPERATION

PAGE 2

ENGLISH

Indoor Unit

Temperature Sensors

Communication

Outdoor Unit

The PCB will signal the louver stepper motor to open the to
either a stationary position or one of several oscillating
modes.
As the louver opens, the PCB will power up the fan motor,
The PCB controls the fan speed if set to the Auto position,

or signals the motor to operate at a ﬁxed speed previously

set.the speed of the fan motor.

The indoor and outdoor unit units communicate via the wire
connected to terminal 3 of each unit.A splice or break in this

wire will cause a communication error.

Upon a request for dry mode, the PCB applies power to the
fan motor outdoor and compressor.Depending on system
cycling, there may be up to a 3 minute wait period before the
compressor and outdoor fan start.

WARNING: Do not measure compressor voltages as damage
to the meter may result.

The PCB also controls the position of the

refrigerant to the evaporator coil.

Use same language here as used in the heating section,
inserting dry mode in place of heat or heating.

Temperature Sensors

Four sensors provide temperature information to the PCB for

control of the system during dry mode.
The ambient sensor provides the temperature of the air drawn

into the condenser coil of the outdoor unit.

The defrost sensor provides the temperature sensed at the
output of the condenser coil.
The suction line sensor provides the temperature sensed at the
incoming suction line pipe.
The 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

Defrost

Protection Functions

1. High Temperature

The PCB monitors the temperature diﬀerence between the

ambient and defrost sensors as the coil becomes colder.

A defrost cycle will initiate when this diﬀerence grows beyond

an acceptable level. To enter a defrost cycle, the compressor
must have accumulated 10 minutes of run time and 45 minutes
of run time since the last defrost.

The discharge (exhaust) sensor monitors the temperature

of the refrigerant leaving the compressor. Compressor
speed will either increase, decrease, or the compressor may
stop in response to temperatures reported by the discharge
sensor. Refer to the table below.

When a call for defrost initiates, the compressor slowly ramps
down, then runs for 30 seconds at a very low speed.

1 minute from the call for defrost, the 4WV switches to cooling,
all fans stop, and the EEV changes to a mid-range. Once these
functions are completed, the compressor ramps up to a high
speed.

When the outdoor coil reaches more than 45 degrees for 60
seconds, or more than 54 degrees for 30 seconds, the defrost
cycle will terminate. The compressor then returns to a very
low speed for 1 minute while all components return to the
heating mode.

The defrost cycle is terminated automatically after 10 minutes

if the coil does not reach the speciﬁed temperatures.

Abnormal stop

Decreasing the frequency rapidly (1HZ/1sec

ond)

230

°F

212

°F

209

°F

199