Everest EGC 100 A / 150 A, Техническое руководство

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33
3.6 - GAS LOAD / REPLACEMENT
OF THE COOLING COMPRESSOR
Check the following items when replacing the compressor (23):
A • The TECUMSEH AE-4430Y (AE-540) or the EMBRACO FF 8.5HBK should be used for the EGC-50A
Ice Machine and the TECUMSEH AE-4450Y (AE-660) or the EMBRACO FFI 12HBX for the EGC-75A,
100A, 150A and 150MA Ice Machines. Check the correct voltage for the compressor (23), as well as
its electrical components (thermal protector and relay).
B • Always replace the cooling filter and if you do not find an identical model (diameter of 3/4" x
120mm long, with molecular MS 594), use a model with the higher dimensions, as similar as
possible.
C • The vacuum recommended for the cooling system is 200 microns Hg for a period of 20 minutes,
using the service pipe of the compressor and the service pipe of the gas filter. When there is no
possibility of creating vacuum through the gas filter (high), i.e., only using the service pipe of the
compressor (23), it is impossible to obtain low vacuum in the condenser line (25,) due to the
resistance offered by the capillary tube. In this case, you should proceed as follows:
• Evacuation of the system up to 1,000 microns Hg.
• Equalization to the atmospheric pressure with R-134a coolant.
• Evacuation of the system up to 500 microns Hg.
These operations aim at obtaining the dilution of non-condensable gases in the system, so that the
volume of these gases is minimal after the second evacuation, as well as promoting the removal of
residual moisture from the system.
D • The R-134a gas load should comply with the table on page 03, General Technical
Characteristics, but when unable to verify the correct weight, a practical way to proceed is to load
the system with gas, switch the machine on, wait for the equipment to complete a cleaning cycle
(page 07), fill the plastic trough (35) with water to the maximum level, considering 5mm below the
rim of the plastic trough (35) and watch the behavior of the gas in the return pipe, next to the
compressor area. If the load is insufficient, it will be observed that the return pipe will remain at
room temperature or slightly cool, and the thickness of the ice on the last evaporator thimbles (20)
will be smaller than on the thimbles near the gas inlet.
In case of excessive gas, the return will freeze up to the compressor inlet (23), which is harmful to
it, as well as reducing the efficiency of the cooling system; Therefore, the optimal load is uniform in
all evaporator thimbles (20) and the return near the compressor (23) becomes cold or perspires.