Vogt HE S Series, Инструкции по установке и запуску

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Installation & Start-up – HES Series
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General Machine Information
Refrigerant Charge. Each HES Series Tube-Ice machine is charged with refrigerant and test operated
at the factory before shipment. The total charge of R-404A is approximately 90lbs. This is not a critical
charge. The operating level indicated on the receiver is intended as an approximate level only. As long
as the machine is operating satisfactorily, there should be no need to add refrigerant. However, as
indicated in the instructions for air-cooled condenser installation, it may be necessary to add refrigerant
to the system for line sets over 75 feet in length.
! CAUTION !
Refrigerant should only be added in the total pumpdown mode.
! CAUTION !
Total Pumpdown Mode. Total pumpdown is initiated by setting the selector switch to the “Clean”
position. The machine will continue to run in the current cycle and proceed to the Total Pumpdown
Mode at the completion of the next harvest cycle. At this time the compressor and water pump will run,
the “A” (liquid feed) solenoid valve will close and the freezer will begin to pump down. As the suction
pressure decreases, the freezer pressure switch will initiate a harvest cycle to clear the partially formed
ice cylinders from the freezer. This harvest cycle will end after one minute and the total pumpdown will
resume, continuing until the compressor cycles off by the low-pressure switch. At this time, only the
water pump will be running.
Note: The liquid line will contain refrigerant from the receiver to the liquid
feed “A” valve (20). Move the selector switch to the “Off” position. The machine is now pumped down.
Note:
If the machine is in the Total Pumpdown mode for an extended period of time, (over 15
minutes for HES-40, over 20 minutes for HES-30, over 25 minutes for HES-20) and the
compressor does not shut off, a problem exists.
If freezer pressure is not pulling down, one of the following problems may be true: liquid feed,
“A” valve (20) or Thaw gas, “D” valve (18) is leaking, or the compressor may be damaged.
If freezer pressure is pulling down but the compressor does not shut off, a problem may exist
with the High/Low pressure safety switch.
Adding Refrigerant.
Once total pumpdown mode is achieved, open the upper and lower gage cock
valves to view the level of refrigerant in the system. Connect a charging hose to the charging valve (28)
located at the base of the evaporator. It is important that no air or other non-condensable gases enter the
system when charging refrigerant into the unit. Open the charging valve to the refrigerant cylinder to
begin feeding
liquid . Turn the selector switch back to the “Clean” position and push the “Harvest/Start”
switch. The water pump will start immediately. The compressor will start as soon as the pressure rises
sufficiently to reset the low-pressure switch. The compressor will pump refrigerant into the receiver as
it is fed into the evaporator. The refrigerant level should rise accordingly in the sight glass. One inch
(1”) is equivalent to 5 lbs. in the receiver. Once the level is within an inch of the target level, close the
charging valve and the compressor will continue until tripping the low-pressure switch. Repeat the
procedure if necessary.
To restart the machine after a total pumpdown, set the selector switch to the “Ice” position and push the
“Harvest/Start” switch. At this time, the “A” (liquid feed) solenoid valve will open for 2 minutes and the
machine will start in a freeze cycle.
! CAUTION !
If the power has been turned off to the machine, make sure the compressor crankcase is warm and
there is no liquid refrigerant in with the oil before restarting the unit.
! CAUTION !