Vollrath Stoelting E111I, Service Manual

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F. Leave the suction and discharge ports open to
prevent pressure buildup. Braze the suction and
discharge line to the compressor.
G. Connect the wires to the compressor terminals.
H. Replace the drier per the instructions in Section
5.9.
I. Evacuate the system per the instructions in Section
5.2
J. Recharge the system per the instructions in
Section 5.3.
K. Replace the insulating tubing on the suction line.
5.5 CONDENSER
The F111 is available with a water-cooled or an air-cooled
condenser. The E111 is available with an air-cooled con-
denser. The capacity of these machines is directly related
to keeping the condenser clean and free of debris.
The water-cooled condenser is a tube and shell type. This
condenser requires cool, clean water to function properly.
Inlet and discharge lines must be 3/8” ID minimum.
The air-cooled condenser is a copper tube and aluminum fin
type. The machine must have a minimum of 3” of clearance
on the sides for proper air flow.
CONDENSER TESTING
The condenser can be checked for leaks using the bubble
test or using a leak detector.
5.6 EVAPORATOR
The E111 & F111 have a freezing cylinder evaporator and a
hopper evaporator.
EVAPORATOR TESTING
The evaporator can be checked for leaks using the bubble
test or using a leak detector.
NOTE
Foam insulation in the evaporator will set off elec-
tronic leak detectors if disturbed.
5.7 VALVES
A. THERMOSTATIC EXPANSION VALVE (TXV)
The Thermostatic Expansion Valve (TXV) is used to meter
the refrigerant to the evaporator. It does so by maintaining
a low, constant superheat in the evaporator. The self-
regulating TXV is preset by the manufacturer and adjust-
ment is not recommended. Figure 5-3.
TXV TESTING & ADJUSTMENT
When testing a TXV, disconnect the hopper liquid line
solenoid.
NOTE
The bulb has an indent which must be positioned
against the tubing. Good contact between the bulb
and the suction line is necessary for proper opera-
tion of the valve. The bulb must also be well insu-
lated.
A. Connect a gauge to the Schrader valve on the
suction line next to the evaporator.
B. Connect a thermocouple to the suction line next to
the evaporator.
C. Immediately before the refrigeration cycle ends,
the gauge should read between 19-22 psig and
superheat should be 10-16°F.
D. If the pressure reading is higher than expected and
the superheat is low, check to see if there is an
overcharge of refrigerant.
E. If the pressure reading is lower than expected and
the superheat is high, check to see if there is a low
refrigerant charge or if there is a restriction in the
system.
NOTE
The TXV is the LAST component to adjust in the
refrigeration system.
F. The TXV can be adjusted after the steps above are
completed. When adjusting, do not turn the valve
over 1/4 turn (90°). Turn the valve stem clockwise
to increase the superheat or counterclockwise to
decrease the superheat.
Figure 5-3 TXV