Presentation on theme: "Basic Refrigeration, Its Components, and Its Cycle"— Presentation transcript:
1 Basic Refrigeration, Its Components, and Its Cycle Mingledorff’s, Inc.Basic Refrigeration, Its Components, and Its Cycle
2 Introduction to Refrigeration Refrigeration: Cooling to preserve products and provide comfort.Types of Refrigeration ProcessesHigh Temperature - Air conditioning (comfort cooling)Medium Temperature - Food preservation (keeping product cool)Low Temperature - Food preservation (freezing of the product)
3 What is Refrigeration? Remember: Heat flows from warm to cold. The process of transferring heat from a place where it is not wanted to a place where it makes little or no difference.Remember: Heat flows from warm to cold.
4 One ton of Air Conditioning = The removal of 12,000 Btu per hour. How Do We Rate Air Conditioning Equipment?One ton of Air Conditioning = The removal of 12,000 Btu per hour.
5 Four Major Refrigeration System Components The evaporatorThe compressorThe condenserThe metering device
7 The Evaporator A heat exchanger to absorb heat Evaporator coil - used to absorb heat from the conditioned space or productLocated on the low side of the sealed system between the metering device and low side of the compressor
8 The EvaporatorOperates at temperatures colder than the medium passing across the coilAbsorbs heat by boiling a low temperature liquid to a low temperature vaporMetering device feeds liquid refrigerant into the evaporator. Under standard conditions, the mixture coming into the evaporator is 75% liquid and 25% vapor
9 The EvaporatorSuperheat - the heating of a vapor above the refrigerant saturation temperatureSuperheat ensures that no liquid returns to the compressorDesign evaporator superheat ranges from 8 to 12 degrees FSuperheat is determined by subtracting the evaporator's saturation temperature from the temperature of the outlet of the evaporator
11 The CompressorPumps heat laden vapor from the evaporator to the condenserThe compressor reduces the pressure on the low side of the systemThe compressor increases the pressure on the high side of the system
12 The CompressorMost common types of compressors used are the reciprocating, the rotary, and the scrollPositive displacement compressors require that the compressed gas be moved into the condenser or damage will occur
15 The CondenserRejects sensible and latent heat from the system that was absorbed by the evaporator and the compressorLocated on the high side of system
16 The CondenserThe heat is released from the refrigerant in the condenser causing it to change state from a high-temperature, high-pressure vapor to a high-pressure high-temperature liquidCondensing temperature is determined by the system's head pressure
17 The CondenserThe condenser normally subcools the liquid at the end of the condenserSubcooling is lowering the temperature of a liquid below saturationStandard air cooled condensers are designed to subcool the liquid by a minimum of 10 degrees F below the saturation temperatureAmount of subcooling is determined by subtracting the outlet temperature of the condenser from the condenser saturation temperature
19 The Refrigerant Metering Device Controls the flow of subcooled liquid refrigerant into the evaporatorOrifice Metering Device-Creates a pressure drop between the high side and low side of the sealed system25% of the liquid leaving the metering device turns to vapor called flash gas