SER VICING PRECAUTIONS
AIR RECHARGING IN COMPRESSORvacuum operation is over, add the quantity in grams of
Test the refrigeration system connecting it electrically beforeR-12(R134a) to the refrigeration system. Remember that
every system has an exact quantity of R-12(R134a) with a
refilling operation. It is necessary to ascertain the function
of the motor-compressor and identify the defectstolerance of ?5 grams that can be added. (Figure 4)
immediately. If defects have been found, empty the old
system of possible R-12(R134a) residue by breaking off the
end of the extension piece at its narrow point. (Figure 1)
Replace the filter and any damaged components. Unsolder
and pull off the piece remaining inside the service tube and
then attach an complete extension with male Hansen and
at last, solder it to the same tube again. (Figure 2)
CHARGE TUBEFEMALETO THE R-12(R134a) CYLINDER
POINT TO BE BROKENEXTENSIONHANSEN
MALE HANSEN
TO THE REFRIGERATION
SYSTEM
Figure 4
SERVICE TUBE EXTENSIONSOLDERING POINT
Before performing this operation (if the vacuum pump andFigure 1Figure 2
refilling cylinder are connected), make sure that the valve
placed between the vacuum pump and the refilling tube are
It is necessary to execute the soldering operation withclosed in order to keep the Freon for addition to the system.
valve open so that the fumes caused by oil residue can(Figure 5)
come out freely without blowholes between two tubesFILLING ORVALVE TO BE OPENED
during the heating the of the point to be soldered.CHARGE TUBEWHEN REFILLING
The extension fitted with the male Hansen is connected to
the female fitting of the vacuum pump tube. (Figure 3)
TO THE REFRIGERATIONTO THE CHARGE
SYSTEMCYLINDER
VALVE TO BE CLOSED
AFTER VACUUM
TO THE
TO THE
VACUUMVACUUMFigure 5
PUMPPUMP
PRESSURE
GAUGEIn addition, check the graduated scale on the cylinder for
the quantity of R-12(R134a)to be added, for example, if we
have 750 grams of Freon in the cylinder and must add 165Figure 3
grams to the group, this amount will be reached when
R-12(R134a) has dropped to 585 grams, remembering that
Air evacuating from the system begins as soon as thethe indicator shows a lower limit of meniscus. Do this after
pump starts. The refrigeration system must be kept underchoosing the scale corresponding to the gas pressure
vacuum until the reading on the low-pressure gaugedifferent scales reported as the same gas pressure
indicates vacuum (0 absolute, -1 atm., -760 mm hg) in anyindicated by the pressure gauge on the top of the column.
case it is advisable to keep the pump running for about 30
To make R-12(R134a) flow into the system, open the valve
minutes. (Figure 3)placed at the base of the cylinder and connected to the
In case that a considerable leakage occurs it will befilling tube. The amount of Freon cannot be added to the
necessary to stop the vacuum pump and to add asmallsystem all at once because it may cause a blocking of motor-
quantity of Freon to the system, if vacuum should not becompressor.Therefore, proceed by adding the original
obtained (pressure gauge can't fall to 1 atmosphere), startquantity of about 20-30 grams and close the valve
the refrigeration unit and find the leakage with the specialimmediately.
leak-finder. When the defective soldering point is visible,The pressure rises and the motor compressor must start
re-do it after opening the extension tube valve andsucking the gas and lowering the pressure again. Regulate
reestablishing the normal outside pressure inside thethe valve again, maintaining the same manner until
group.
reaching to the quantity of R-12(R134a) established for the
Because the melted alloy is sucked into the tubes andsystem being charged. When the system is running, the
block them, the pressure must be rebalanced whensuction pressure must be stabilized between 0.30 to
vacuum is in the system in soldering. As soon as the0.6(0.10 to 0.4) atmosphere. |
ACEC
