Vollrath Stoelting E111I, Руководство по обслуживанию

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TXV REMOVAL
A. Disconnect the machine from the electrical supply
before removing any panels for servicing.
B. Remove the side panel.
C. Remove bulb from suction line exiting from the
evaporator.
D. Recover refrigerant charge per instructions in
Section 5.2.
E. Leave the suction and discharge ports open to
prevent pressure buildup during TXV removal.
F. Remove any insulation from the TXV and
immediate surrounding lines.
G. Apply a heat sink (wet cloth) to the valve dome.
H. Unsweat the TXV and remove.
TXV REPLACEMENT
To replace the TXV, perform the following procedures:
A. Position the TXV with a heat sink into the system.
B. With the suction and discharge ports open, braze
the TXV into the system using appropriate brazing
material.
C. Remove the heat sink from the TXV.
D. Install bulb on suction line exiting the evaporator
using existing clamp. The bulb has an indent
which must be placed against the tubing.
NOTE
Good contact between the bulb and the suction line
is necessary for proper operation of the valve. The
bulb must also be well insulated.
E. Tighten clamp to 20 in/lb using a torque wrench.
F. Replace insulation to the TXV and surrounding
lines.
G. Replace the drier per the instructions in Section
5.9.
H. Evacuate the system per the instructions in Section
5.2.
I. Recharge the system per the instructions in
Section 5.3.
B. CHECK VALVE
The refrigeration system has 2 magnetic check valves
(Refer to Figure 5-4). Each valve is positioned in the suction
line and prevents backflow of refrigerant into an evaporator.
If there is reversed flow, the product in the freezing cylinder
softens and liquid refrigerant can flood into the compressor
on startup.
If a check valve needs to be replaced, use a heat sink (wet
cloth) when installing the new valve to prevent damage.
C. HIGH PRESSURE CUTOUT
The high pressure cutout stops the compressor if the
discharge pressure reaches 445 psig.
HIGH PRESSURE CUTOUT TEST
A. Connect a gauge to the Schrader valve on the
discharge line.
B. Disconnect cooling:
Air-Cooled - Disconnect evaporator fan
Water-Cooled - Shut off water supply
C. High pressure cutout should trip when pressure
reaches 445 psig ±9.
Figure 5-4 Check Valve
Figure 5-5 High Pressure Cutout