CONDENSOR
In the condenser,the compressed refrigerant vapours emit the heat collected in the evaporator and during compression.Condensation heat is removed by either cooling water or cooling air.
Poor condenser cooling leads to reduced compressor capacity and increase power consumption.The increased discharge pressure reduce the expected lifetime of the compressors and can even cause some of the components to explode.
However,too much condenser cooling reduces the discharge pressure.
Air cooled condensers
Air cooled condensers can be regulated as follows :
a. Controlling the fan speed,either by start/stop or with pole-changeable motors (the first method is to be preferred).
b. Using dampers to throutle the air flow.
c. Partially filling the condenser with liquid refrigerant. An automatic valve is used to limit the condenser discharge. This method is particularly good when the refrigeration plant is only slightly loaded.
d. The condenser can be split into sections,which can be coupled out and.
Water cooled condensers
Water cooled condensers can be regulated by throttling the flow of water through the condenser.
a. Manual regulation is considered to be adequate in many cases-a more or less constant discharge temperature can be maintained. A two or three way regulating valve can be fitted in the by pass.
b. Automatic water valves :
- Directly pressure controlled
Two way water valves are used in plants with small compressor nits or if cooling water is readily available.
The amount of water is regulated by impulse from the discharge pressure,the valves opens when the pressure rises and shuts when it falls.
- Temperature controlled
In a temperature regulated water valve,The amount of cooling water is regulated by a servo valve which receives impulses from sensor,place in the return line after the condenser. A three a way valve is often fitted in the by pass to ensure that the pump supplies a constance amountof water.
In the condenser,the compressed refrigerant vapours emit the heat collected in the evaporator and during compression.Condensation heat is removed by either cooling water or cooling air.
Poor condenser cooling leads to reduced compressor capacity and increase power consumption.The increased discharge pressure reduce the expected lifetime of the compressors and can even cause some of the components to explode.
However,too much condenser cooling reduces the discharge pressure.
Air cooled condensers
Air cooled condensers can be regulated as follows :
a. Controlling the fan speed,either by start/stop or with pole-changeable motors (the first method is to be preferred).
b. Using dampers to throutle the air flow.
c. Partially filling the condenser with liquid refrigerant. An automatic valve is used to limit the condenser discharge. This method is particularly good when the refrigeration plant is only slightly loaded.
d. The condenser can be split into sections,which can be coupled out and.
Water cooled condensers
Water cooled condensers can be regulated by throttling the flow of water through the condenser.
a. Manual regulation is considered to be adequate in many cases-a more or less constant discharge temperature can be maintained. A two or three way regulating valve can be fitted in the by pass.
b. Automatic water valves :
- Directly pressure controlled
Two way water valves are used in plants with small compressor nits or if cooling water is readily available.
The amount of water is regulated by impulse from the discharge pressure,the valves opens when the pressure rises and shuts when it falls.
- Temperature controlled
In a temperature regulated water valve,The amount of cooling water is regulated by a servo valve which receives impulses from sensor,place in the return line after the condenser. A three a way valve is often fitted in the by pass to ensure that the pump supplies a constance amountof water.
refrigeration
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