From its experience RefComp has developed the new 4-cylinder semi-hermetic compressors of its P series: the range of the reciprocating 4, 6 and 8-cylinder P compressors is now including also eight 4-cylinder models with increased motor power (from 6 up to 20 Hp) and increased displacement at 50 Hz (from 35 up to 67,2 m3/h).

The new compressor models are proposed in two different configurations: with forced lubrication (through oil pump) or with  splasher lubrication (by centrifugation into an oil thrower disc).

The continuous research for innovative design solutions and for modern manufacturing techniques has resulted in an extension of the typical features of the semi-hermetic P compressors also to the new models, that are versatile, energy efficient, noiseless and reliable.

These compressors are characterized by an extreme flexibility and by a wider application field:

- this series can be used with both HFC refrigerants (R404A/R507, R407C or R134A) and R22;
- the compressors can be supplied either with “full size” electric motors for air conditioning systems or with “small size” electric motors for refrigeration systems;
- motors with special frequencies or voltages are available to suit a wide variety of applications;
- on request the compressors can be delivered with a fan for additional cooling or kit for liquid injection including the control module (LCM) in order to reduce the discharge temperature;
- on request the compressors can be delivered with optional Start Unloading System (SU).

The optional 1-step integrated capacity control (100-50-0%), achieved by the exclusion of two cylinders, leads to a reduction of the cooling capacity, thus to a decreased absorbed current, assuring a high efficiency even at part load operations.

The optional self-regulating PTC crankcase heater is aimed to a reduction of the absorbed current within an energy saving philosophy.

Particular attention has been given to the dimensioning of the components in order to reduce the sound and vibration level and granting the utmost compression efficiency also thanks to:
- new reed valves offering the highest resistance to fatigue cracks and shocks;
- suction side cleaning filter with fine mesh designed to capture impurities in the cooling circuit;
- oil filter with large surface area (only for models with forced lubrication);
- optional opto-electronic controls (for models with splasher lubrication) or electromechanical controls (for models with forced lubrication);
- electrical motor, Class F, fitted with PTC temperature sensors embedded in the windings;
- electronic control unit for a continuous monitoring of the motor temperature, thanks to the PTC thermal probes, and of the discharge temperature, thanks to the related optional sensor.

Typical features of these P compressors are also the new cast iron casing, the compact structure and the easy installation: the dimensions and the position of the connections are compliant to international standards; the terminal box (protection class IP54) is designed for an easy connection to the power and electric motor protection circuits.

RefComp products are up to EU-directives, such as the Machinery Directive 98/37/EC, the Low Voltage Directive (LVD) 73/23/EEC and the Electromagnetic Compatibility Directive 89/336/EEC – 92/31/EEC.

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