Chicago Pneumatic CPF 175, Instruction Book

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Air flow
Air-cooled compressor
Air drawn through filter and unloader (UA) is compressed in compressor element (E). Compressed air and
oil are discharged through check valve (CV) to air receiver/oil separator (AR) where oil is separated from the
compressed air. The air is blown through minimum pressure valve (Vp) to air cooler (Ca).
The cooled air is discharged through the outlet towards the air net. An optional condensate trap may be
provided between the air cooler and outlet valve.
Check valve (CV) prevents blow-back of compressed air.
Minimum pressure valve (Vp) prevents the receiver pressure from dropping below a minimum pressure.
Oil system
Air pressure forces the oil from receiver (AR) through oil cooler (Co), filters (OF), oil stop valve (Vs) and an
oil injection valve to the compressor element (E) and the lubrication points. On air-cooled compressors, an
oil injection valve will open at higher ambient temperatures to keep the element outlet temperature low.
For air-cooled units, the oil temperature is controlled by regulating the speed of the fans (FN), to avoid
overcooling and consequently condensation in the air receiver (AR).
On air-cooled compressors with energy recovery or on water-cooled compressors, the oil temperature is
controlled by a thermostatic valve to avoid overcooling and consequently condensation in the air receiver
(AR).
In the air receiver (AR) most of the oil is removed from the air centrifugally. Almost all of the remaining oil
is removed by the separator element.
Instruction book
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