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2. Features and benefits
TCGB0075 rev.0 - 11/2012
31
2
High pressure shell
• It acts as an oil separator reducing the amount of oil circulating in the cooling system giving better heat exchanger
efficiency.
•
Motor heat is not added to the suction gas before compression, which reduces the discharge gas temperature. This is
particularly important at low suction temperatures. The discharge gas cools the motor sufficiently.
•
Refrigerant cannot enter the shell during the off cycle causing oil dilution and oil foaming at start up.
• System of regulating pressure, increasing the compressor’s efficiency and reliability in part load mode. This system
ensures the work pressure of the compressor is always at optimum level regardless of the charge, so that the ratio
between the discharge pressure (Pd) and the suction pressure (Ps) is optimum as in the following graphic:
Pd
Ps
Overcompression
zone based
on the new pres-
sure regulation
system
Volume
Pressure
Lubrication
Bearing in mind that lubrication is one of the most important factors in the service life of a compressor, HITACHI has deve-
loped a system based on the pressure differences between the suction and discharge using a secondary pump at the base
of the compressor. As a result, all of the compressor’s moving parts are lubricated evenly, ensuring high reliability in terms
of its operating range, even at low frequencies.
Hitachi Air Conditioning Product SA 2008
.
1. Comercial information
MAIN FEATURES
Discharge
Roller Bearing
Synchronous
motor
Asymmetric Scroll
Oil Return Pipe
Sub-ball-bearing
structure
Trochoid oil pump
Suction