53
Next, the installer will enter the
WEIGH IN
screen to verify the current total charge
is accurate. Once the installer has confirmed, touch
DONE.
Next, the installer will enter the
SERVICE VALVE SUBCOOL
screen. This screen
will show the current liquid line subcool target (in
_
F). To begin the charging, touch
START
.
Next, the installer will enter the
SERVICE VALVE INFORMATION
screen. The
current liquid line subcool target, stabilization time, mode and speed in rpm, EXV
position in percent, indoor airflow in CFM, outdoor coil temperature in
_
F, indoor
temperature in
_
F, outdoor temperature in
_
F, compressor discharge pressure in
psig, and accumulator suction pressure in psig are displayed on this screen. Once
the stabilization time has expired, touch
DONE
.
6.6.2.
Pump down
Because this system has an inverter controlled compressor, suction pressure
transducer and EXV, conventional procedure cannot be used to “pump down” and
isolate the refrigerant into the outdoor unit. The control has provisions to assist in
performing this function.
S
Select mode to pump down in (
COOL
or
HEAT
).
COOL
mode allows
refrigerant to be isolated in outdoor unit.
HEAT
mode allows the refrigerant to
be isolated in indoor coil and lineset. Set desired time period.
d
Default time period for procedure is 120 minutes.
S
Touch
START
to begin the pump down process. Unit will begin running in
selected mode after a brief delay.
6.6.3.
Evacuation
Because this system has an EXV for the heating expansion device, additional steps
must be taken to open the EXV if the heat pump unit must be evacuated for service
reasons. If the EXV is not open when pulling a vacuum or recovering refrigerant
from the heat pump unit, extended evacuation time may be required and/or