The refrigerant when it is vapour state that time it carry lower temperature and lower pressure than the regular one and enters to the compressor of the vapor compression refrigeration cycle from the evaporator of the system. After enter to the evaporator the vapour became carry higher temperature as well as higher pressure.
What is the function of compressor in refrigeration system?
Function of compressor is, “to compress low pressure, low temperature vapour refrigerant to convert it into high pressure, high temperature vapour refrigerant”.
What happens to the refrigerant when it enters the compressor?
In normal conditions, the refrigerant enters into the Compressor in a gaseous state from the evaporator. But due to certain factors, the liquid refrigerant returns to the Compressor in large volume through the suction pipe. The evaporator is responsible for the refrigeration effect in the HVAC system.
What is the working principle of a compressed hot refrigerant?
The compressed hot refrigerant liquid is cooled in the condenser and sent through the expansion valve into the evaporator. At the inlet of the evaporator, the refrigerant is a mixture of gas and liquid at low pressure. The refrigerant takes heat from ambient air (causing the cooling effect) in the evaporator and transforms it to vapor form.
What happens to refrigerant when pressure is reduced?
The changing of state within the refrigerant, from a liquid to a gas, is achieved by manipulating its pressure. Under high pressure the refrigerant remains in its liquid state, and when the pressure is reduced the liquid refrigerant begins to ‘boil’ and change in to a vapour or gas.
What happens to the system refrigerant during compression?
Stage 1: Compression The compressor compresses the refrigerant to a high-pressure vapor, causing it to become superheated. Once the refrigerant is compressed and heated, it leaves the compressor and enters the next stage of the cycle.
What is the low pressure side and high pressure side of the refrigeration cycle?
Two different pressures exist in the cycle - the evaporating or low pressure in the "low side," and the condensing, or high pressure, in the "high side." These pressure areas are separated by two dividing points: one is the metering device where the refrigerant flow is controlled, and the other is at the compressor, ...
What components in a compression refrigeration system maintain the pressure difference in the system?
To maintain the difference in pressure between the condenser and the evaporator caused by the compressor, an expansion valve is needed in the cycle. The expansion valve separates the high-pressure part of the system from the low-pressure part. Only a small trickle of refrigerant liquid flows through the valve.
What part of a refrigeration system controls the flow of refrigerant from high pressure to low pressure?
The condenser This component is supplied with high-temperature high-pressure, vaporized refrigerant coming off the compressor. The condenser removes heat from the hot refrigerant vapor gas vapor until it condenses into a saturated liquid state, a.k.a. condensation.
Which of the following reduces high pressure and high temperature refrigerant to low pressure and low temperature refrigerant?
Expansion Valve: This device removes pressure from the liquid refrigerant to allow expansion or change of state from a liquid to a vapor in the evaporator.
What causes low pressure in refrigeration?
Many reasons can cause low refrigerant suction pressure, i.e.: low indoor temperature, dirty filters, restricted ducts, undersized ducts, closed dampers, frosted coils, restricted refrigerant line, restricted piston, incorrect piston, restricted strainer, bad indoor blower motor ect.
Why is low pressure refrigerant given to evaporator?
The refrigerant enters the evaporator as a cold, low pressure liquid, the refrigerant begins to boil and evaporate, this evaporation causes a cooling effect in the room and the heat is carried away to be dumped in the condenser after the compressor.
Why boiling point of refrigerant should be low?
The refrigerant should have a low boiling point and low freezing point. It must have low specific heat and high latent heat. Because high specific heat decreases the refrigerating effect per kg of refrigerant and high latent heat at low temperature increases the refrigerating effect per kg of refrigerant.
Where does refrigerant go when it leaves the purge unit?
Question #1: After the refrigerant leaves the purge unit, where does it go? The refrigerant from the purge unit free from air and moisture enters the evaporator through the expansion valve.
What should the pressure of the low side and high side a C system read on a gauge set with the engine off?
An A/C System that is working properly should have 150 PSI on the high side and 30 PSI on the low side.
Which components separate the high side from the low side in a refrigerant system?
At this point, the refrigerant is a superheated gas. Compressor: This device has two purposes, due to the fact that it separates the low-pressure side of the system from the high-pressure side.
When the refrigerant enters the compressor What state is it in?
superheated vaporQuestion #4: When the refrigerant enters the compressor, what state is it in? After the evaporator, all of the refrigerants has heated beyond its boiling point, making it a superheated vapor. This means that from the evaporator, entering into the compressor, the refrigerant is in the superheated vapor state.
Which is the high and low side of refrigeration system?
This system is referred to as having two sides: a low pressure or low side, where the refrigerant absorbs heat as it evaporates, and a high pressure or high side, where the refrigerant vapor releases heat as it is condensed back into a liquid.
Which is high side on refrigerator?
The high side of the refrigeration system consists of a condenser and a receiver. Warm refrigerant vapor enters the condenser after it has been pressurized by the compressor. A condenser will typically use air and water to cool the warm ammonia as it passes through a series of tubes within the condenser.
Which is low side in fridge?
The low side of a refrigeration system usually houses the evaporator, suction line, and any accessory components located within the suction line. Accessory components can include evaporator pressure regulator valves, suction filters and driers, crankcase pressure regulator valves, and suction accumulators.
What should the pressure of the low side and high side a C system read on a gauge set with the engine off?
An A/C System that is working properly should have 150 PSI on the high side and 30 PSI on the low side.
What is the difference between condensing and evaporating pressure?
Here is a summary of some of the definitions used in this column. Condensing pressure: The pressure at which the refrigerant is phase changing from a vapor to a liquid. Evaporating pressure: The pressure at which the refrigerant is phase changing from a liquid to a vapor.
What is the process of a liquid refrigerant changing to a vapor at a constant temperature?
The heat energy that causes a liquid refrigerant to change to a vapor at a constant saturation temperature for a given pressure is referred to as a latent heat process. Latent heat is heat energy that causes a change in phase of a substance without a change in the temperature of the substance.
What is evaporating pressure?
The evaporating pressure is the pressure at which the refrigerant is phase changing from a liquid to a vapor. This phase change is referred to as evaporation or vaporizing, thus the term evaporating pressure. A pressure gauge placed anywhere between the metering device outlet and the compressor will read the evaporating pressure. Again, negligible pressure drops are assumed.
What happens when liquid and vapor are saturated?
Any time there is saturated liquid and vapor together, as in the condenser and evaporator, there will be vapor pressure present. Vapor pressure acts equally in all directions and affects the entire low or high side of a refrigeration system. As pressure increases, saturation temperature increases.
What is condensing pressure?
The condensing pressure is the pressure at which the refrigerant is phase changing from a vapor to a liquid. This phase change is referred to as condensation. Thus the term condensing pressure. This pressure can be read directly from a pressure gauge connected anywhere between the compressor's discharge valve and the entrance to the metering device, assuming that there is negligible pressure drop.
What happens when you raise the temperature of a saturated liquid?
In fact, if one attempts to raise the temperature of a saturated liquid above its saturation temperature, vaporization of the liquid will occur. If one attempts to lower the temperature of a saturated vapor below its saturation temperature, condensation will occur. Both vaporization and condensation occur in the evaporator ...
What is the process of changing a liquid to a vapor?
The heat energy that causes a liquid refrigerant to change to a vapor at a constant saturation temperature for a given pressure is referred to as a latent heat process . Latent heat is heat energy that causes a change in phase of a substance without a change in the temperature of the substance. Phase changes go from liquid to vapor, or from vapor to liquid.
What is the function of a condenser?
The Condenser cools and condenses the refrigerant gas coming from the compressor in to a vapour and finally in to a liquid. 3. The Restriction. The restriction restricts the liquid refrigerant flow and creates a pressure difference between itself and the evaporator.
Why does a refrigerant flash off?
Additional cooling inside the condenser causes the refrigerant vapour to condense in to a high pressure subcooled liquid. As the high pressure liquid refrigerant passes through the metering device it enters a low pressure environment, causing it to flash off in to a vapour.
How does refrigerant heat up?
The refrigerant vapour enters the evaporator where it absorbs heat from the space being cooled, causing the refrigerant to boil. As it continues through the evaporator coil the vapour is superheated turning the refrigerant to gas before it enters the compressor and starts the cycle over again.
What happens to the refrigerant as it goes through the evaporator coil?
As it continues through the evaporator coil the vapour is superheated turning the refrigerant to gas before it enters the compressor and starts the cycle over again. And there it is. The refrigeration cycle in its most basic and understandable terms. For further information on the process click here.
What is subcooling in refrigeration?
SUBCOOLING – Is an amount of heat removed from the refrigerant below its condensing point. This ensures the refrigerant is in a liquid state with no gas present.
What does "saturated" mean in refrigeration?
SATURATED – Is when the refrigerant is a vapour with both liquid & gas present.
How does a refrigerant change from liquid to gas?
The changing of state within the refrigerant, from a liquid to a gas, is achieved by manipulating its pressure. Under high pressure the refrigerant remains in its liquid state, and when the pressure is reduced the liquid refrigerant begins to ‘boil’ and change in to a vapour or gas. If we return to the refrigeration cycle with the aid ...
What is a condenser coil?
The condenser. The condenser, or condenser coil, is one of two types of heat exchangers used in a basic refrigeration loop. This component is supplied with high-temperature high-pressure, vaporized refrigerant coming off the compressor. The condenser removes heat from the hot refrigerant vapor gas vapor until it condenses into a saturated liquid ...
What happens to the refrigerant after condensing?
condensation. After condensing, the refrigerant is a high-pressure, low-temperature liquid, at which point it’s routed to the loop’s expansion device.
How does a fan cool a refrigerant?
This happens when refrigerant enters the evaporator as a low temperature liquid at low pressure, and a fan forces air across the evaporator’s fins, cooling the air by absorbing the heat from the space in question into the refrigerant .
What is the first step in the refrigeration cycle?
The compressor. Compression is the first step in the refrigeration cycle, and a compressor is the piece of equipment that increases the pressure of the working gas. Refrigerant enters the compressor as low-pressure, low-temperature gas, and leaves the compressor as a high-pressure, high-temperature gas.
What is the second heat exchanger in a refrigeration circuit?
The evaporator. The evaporator is the second heat exchanger in a standard refrigeration circuit, and like the condenser, it’s named for its basic function. It serves as the “business end” of a refrigeration cycle, given that it does what we expect air conditioning to do – absorb heat.
What is a refrigeration cycle?
In simple terms, a refrigeration cycle's mission is heat absorption and heat rejection. As any HVAC instructor will tell you (emphatically), you can't make cold, you can just remove heat. The refrigeration cycle, also called a heat pump cycle, is a means of routing heat away from the area you want to cool. This is accomplished by manipulating the ...
What are the components of a basic cycle?
There are certainly other components in most loops, but most would agree the four fundamental elements of a basic cycle are as follows: The compressor. The condenser. The expansion device. The evaporator.
What is the role of the evaporator in HVAC?
The evaporator is responsible for the refrigeration effect in the HVAC system. The compressed hot refrigerant liquid is cooled in the condenser and sent through the expansion valve into the evaporator. At the inlet of the evaporator, the refrigerant is a mixture of gas and liquid at low pressure. The refrigerant takes heat from ambient air (causing the cooling effect) in the evaporator and transforms it to vapor form. It enters into the compressor suction in the vapor form.
What happens when refrigerant is not vaporized?
When in an HVAC system, the refrigerant is not entirely vaporized inside the evaporator, then liquid refrigerant directly touches the crankcase of the Compressor. This situation mainly occurs in an operating condition frequently faced by the servicing technicians, popularly known as Flooding.
What is the role of a compressor in the refrigeration cycle?
We all know that the heart pumps blood throughout the human body; in the same way, a Compressor enables the flow of the refrigerant throughout the refrigeration cycle.
Why does a compressor fail?
Analysis reveals that entry of liquid refrigerant in Compressor during the running cycle is one of the primary reasons for Compressor failure .
What is the continuous flow of liquid refrigerant into the compressor in oil droplets instead of superheated?
The continuous flow of liquid refrigerant into the Compressor in oil droplets instead of superheated vapor is known as Compressor Flood back.
Why does my compressor make a knocking sound?
A loud knocking sound arises due to Slugging.
How does a piston move?
A piston moves inside a cylinder to help in and out of gas in the Compressor. The high-pressure hot refrigerant gas from the Compressor is then pushed into the condenser. The refrigerant comes out from the condenser as a high-pressure liquid that enters the evaporator through the expansion valve.