utopia dc-inverter es series hvrn1/h(v)rns(e) - AB Klimatizace, s.r.o.

Benefits of DC Inverter
Main features of the units:
Newlydevelopped
scroll for
410A
New drive
mechanism
Oil feeding
mechanism etc.,
DC Inverter
Motor
51
Highly efficient scroll compressor exclusive to Hitachi
- Compact design
The new HITACHI DC INVERTER scroll compressor has been developed to
increase efficiency, reliability and power consumption.
- 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.
- New system of regulating pressure (only for RAS-4~6HVRNSE), 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:
TCGB0052-rev.1-07/2009
Pressure
Pd
Ps
Volume
Overcompression zone based on
the new pressure regulation system
- Lubrication
Bearing in mind that lubrication is one of the most important factors in the service
life of a compressor, HITACHI has developed 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.
- Protection against liquid return
When the compressor is at rest, the moving scroll rests on the casing. When the
compressor starts to run, the pressure in the chamber under the scroll builds
up through two bleed holes in the medium pressure section of the compression
stroke. This pressure then forces the scroll up against the housing and seals the
compression chamber. If liquid returns to the compressor, the resulting increase
in pressure forces the scroll downwards, breaking the seal and allowing the liquid
to pass back into the compressor body, where it will boil off due to the higher
temperature.
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