Zamil MAC-240, Installation, Operation & Maintenance Manual

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3.3.7 Hot Gas By-Pass Control
Hot gas bypass control is provided in the both circuit to permit operation of the system down to 80 % of its unloaded
capacity. Under low ambient condition, it controls temperature by eliminating the need to cycle the compressor on and
off, ensuring narrow temperature swing and lengthen the life span of the compressor.
3.3.8 Crankcase Heater
Each compressor has crankcase heater. The compressor crankcase heater is always on when the compressor is de-
energized. This protects the system against refrigerant migration, oil dilution and potential compressor failure.
3.3.9 Replaceable Core Filter Drier
Refrigerant circuits are kept free of harmful moisture, sludge, acids and oil contaminating particles by the filter drier.
3.3.10 Sight Glass
Moisture indicating sight glass installed in the liquid line. Easy to read color indicator shows moisture contents and
provides a mean for checking the system refrigerant.
3.3.11 Fan Cycle Head Pressure Control
The capacity of air-cooled condensers varies with the difference between condensing temperature and condenser enter-
ing air temperate (ambient temperature). It increases as this difference increases. For a given capacity, a drop in the
ambient temperature will lower the condensing temperatures and if the ambient temperature drops below a given limit,
head pressure control is required. Control shall be set for a minimum of 95°F (35°C) saturated refrigerant condensing
temperature, or to suit the specified application.
3.3.12 Condenser Coil Grills (Guard)
Protect the condenser coil from physical damage.
3.3.13 Discharge Line Mufflers
Discharge line mufflers are installed to eliminate noise due to refrigerant pulsation.
3.3.14 Vibration Eliminator
To eliminate the vibration transmitted from compressor to the piping, unit structure and transportation.
3.3.15 Safety Valve
This valve protects the unit against high discharge pressure in the system due to malfunction of high pressure
switches.