Reduction in pressure below atmospheric pressure

Special high efficiency compressor used for creating high vacuums for testing or drying purposes

Device used for controlling fluid flow

Type of refrigerant control which maintains pressure difference between high side and low side pressure in refrigerating mechanism. Valve is caused to operate by pressure in low or suction side. Often referred to as an automatic expansion valve or AEV

Part of compressor located between top of compressor body and head which contains compressor valves

Device used by service technicians to check pressures and charge refrigerating units

Valve actuated by magnetic action by means of an electrically energised coil

Valve in refrigeration compressor which allows vaporized refrigerant to enter cylinder from suction line and prevents its return

Most water cooling units are supplied with water valves. These valves provide a flow of water to cool the system while it is running. Most water valves are controlled by solenoids

Word usually used to denote vaporized refrigerant rather than the word gas

Thin plastic or metal foil sheet used in air conditioned structures to prevent water vapour from penetrating insulating material

Lines and component parts of system which are charged at the factory

Pressure impassed by either a vapour or gas

Graphic presentation of various pressures produced by refrigerant under various temperatures

A vapour condition which will result in condensation into droplets of liquid as vapour temperature is reduced

Type of belt that is commonly used in refrigeration work. It has a contact surface which is in the shape of letter V

Term used to describe resistance of flow of fluids

Liquid which evaporates at low temperature and pressure

Term used to indicate the electrical potential or electromotive force in an electrical circuit. It is voltage or electrical pressure which causes current to flow

It is necessary to provide some electrical circuits with uniform or constant voltage. Electronic devices used for this purpose are called voltage controls

Instrument for measuring voltage action in electrical circuit

Term used to express the relationship between the actual performance of a compressor or of a vacuum, pump and calculated performance of the pump based on its displacement versus its actual pumping ability