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O−Discharge Line Thermostat (S5)
S5 is an automatic reset SPST N.C. switch which opens on
temperature rise. S5 is located on the discharge line and
wired in series with S4 high pressure switch on the defrost
control board. When discharge line temperature rises to
275° + 8°F the switch opens and shuts down the compres-
sor. The switch resets when discharge line temperature
drops to 225° + 11°F.
P−Dual Capacitor (C12)
The compressor and fan in HPXA19−024, −036, −048 and
−060 units use permanent split capacitor motors. A single
dual" capacitor is used for both the fan motor and the com-
pressor (see unit wiring diagram). The two sides (fan and
compressor) of the capacitor have different mfd ratings and
may change with each compressor. The capacitor is located
inside the unit control box.
Q−Condenser Fan Motor (B4)
HPXA19−024, −036, −048 and −060 units use single−phase
PSC fan motors which require a run capacitor. The FAN"
side of the dual capacitor is used for this purpose. In all
units, the outdoor fan is controlled by the compressor con-
tactor. See ELECTRICAL DATA and SPECIFICATIONS
section for more information. See figure 11 if condenser fan
motor replacement is necessary. Rain shield location is
critical on the condenser fan assembly. Two shields are
used in unison to prevent moisture from entering the motor
bearings. Installing the shields to close to the bearing hub
will create noise and may affect operation. Installing too far
away will allow moisture to enter the bearing, resulting in
motor failure. See figure 12.
FIGURE
11
"A" SEE TABLE 3
FAN
GUARD
Condenser fan
and motor
Wiring
Drip loop
TABLE 3
HPXA19 UNIT
"A" DIM.
+ 1/8"
−024, −036
1 1/16"
−038
−048
1 3/16"
−060
FIGURE 12
Critical Dimension
1/4" (.250)
plastic
shield
fiber
shield
RAIN SHIELD LOCATION
(See figure 14 for HPXA19−038)
FIGURE 13
HPXA19 PARTS ARRANGEMENT
outdoor fan
(variable speed
on 038 units)
start capacitor
(−024 unit only)
system
operation monitor
contactor
defrost control
discharge line
compressor terminal plug
two−stage compressor
vapor line
low pressure switch
high pressure switch
filter drier
vapor valve
and
gauge port
TXV/check valve
charge compensator
(−038 and −048 units)
discharge temperature
thermostat
run capacitor
