SystemAir MCV 15 Manuel D'installation page 14

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The direct expansion coil will be cold only in the portion near the distributor pipes which
could even be frozen (frosted) whereas the return pipes to the compressor are not cold
yet.
As the loading process continues the liquid seen through the sight glass will become clearer and will
fill up with refrigerant in its liquid state:
Stop the compressor
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Shut the cylinder and check that the manometer on the suction line indicates a pressure greater
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than 4 bar (R22 and R407c) or 1 bar (R134a).
Restart the compressor.
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Continue the loading process until through the sight glass one sees only very few small bubbles
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of Freon gas.
At this point the system is fully loaded with gas and the cylinder can be removed leaving, however, the
manometers connected to check that the evaporating and condensing pressures are as per design
pressures.
Example (configuration 2):
Air entering evaporator +24° C.
Evaporating temperature +5° C.
Air entering evaporator +22° C.
Evaporating temperature +4° C.
Air entering condenser +20° C
Condensing temperature +38° C.*
Air entering condenser +25° C
Condensing temperature +43° C.*
Air entering condenser +30° C
Condensing temperature +48° C.*
Air entering condenser +32° C
Condensing temperature +50° C.*
Air entering condenser +35° C
Condensing temperature +52° C.*
3OHDVH QRWH : there can be different condensing temperatures if the low ambient kit
(modulating) has been fitted to the air conditioning unit.
To properly complete the loading of the refrigeration circuit, especially in the case of air-cooled units, it
is necessary to satisfy all the design conditions regarding the temperature of the condensing liquid and
that there is a sufficient heat-load within the ambient; in this way the refrigeration circuit will operate (at
ambient design conditions) for a long enough time to allow one to verify that the entire system is
running correctly.
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