Goodman [A/G]PG, Инструкция по эксплуатации

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PRODUCT DESIGN
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Refrigerant flow control is achieved by use of restrictor orifices
or thermostatic expansion valves (TXV).
The single phase units use permanent split capacitors (PSC)
design compressors. Starting components are therefore not
required. A low MFD run capacitor assists the compressor to
start and remains in the circuit during operation.
The outdoor fan and indoor blower motors are single phase
capacitor type motors.
Air for condensing (cooling) is drawn through the outdoor coil
by a propeller fan, and is discharged vertically out the top of
the unit. The outdoor coil is designed for .0 static. No addi-
tional restriction (ductwork) shall be applied.
Conditioned air is drawn through the filter(s), field installed,
across the evaporator coil and back into the conditioned space
by the indoor blower.
Some APG/GPG series package units use a two-stage scroll
compressor. The two-step modulator has an internal unload-
ing mechanism that opens a bypass port in the first compres-
sion pocket, effectively reducing the displacement of the scroll.
The opening and closing of the bypass port is controlled by an
internal electrically operated solenoid.
The ZPS/ZRS two-step modulated scroll uses a single step of
unloading to go from full capacity to approximately 67% ca-
pacity.
A single speed, high efficiency motor continues to run
while the scroll modulates between the two capacity steps.
Other A/GPG series package units use the Compliant Scroll
compressor, instead of traditional reciprocating compressor.
A scroll is an involute spiral which, when matched with a mat-
ing scroll form as shown, generates a series of crescent shaped
gas pockets between the two members.
During compression, one scroll remains stationary (fixed scroll)
while the other form (orbiting scroll) is allowed to orbit (but not
rotate) around the first form.
As this motion occurs, the pockets between the two forms are
slowly pushed to the center of the two scrolls while simulta-
neously being reduced in volume. When the pocket reaches
the center of the scroll form, the gas, which is now at a high
pressure, is discharged out of a port located at the center.
During compression, several pockets are being compressed
simultaneously, resulting in a very smooth process. Both the
suction process (outer portion of the scroll members) and the
discharge process (inner portion) are continuous.
Some design characteristics of the Compliant Scroll compres-
sor are:
• Compliant Scroll compressors are more tolerant of liquid
refrigerant.
NOTE : Even though the compressor section of a Scroll
compressor is more tolerant of liquid refrigerant, continued
floodback or flooded start conditions may wash oil from the
bearing surfaces causing premature bearing failure.
• Compliant Scroll compressors use white oil which is com-
patible with 3GS. 3GS oil may be used if additional oil is
required.
• Compliant scroll compressors perform "quiet" shutdowns
that allow the compressor to restart immediately without
the need for a time delay. This compressor will restart even
if the system has not equalized.
NOTE: Operating pressures and amp draws may differ from
standard reciprocating compressors. This information can
be found in the unit's Technical Information Manual.
ELECTRICAL WIRING