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علم سیستمهای تهویه مطبوع. تهیه کننده: محسن اشکذری. Himech.wordpress.com. What is 'Air Conditioning'?. Air Conditioning is the simultaneous control of Temperature, Humidity, Motion & Purity of the atmosphere in confined Space. What are the Requirements of comfort Air Conditioning? - PowerPoint PPT PresentationTRANSCRIPT
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: محسن کننده : تهیه محسن کننده تهیهHimech.wordpress.comHimech.wordpress.comاشکذریاشکذری
What is 'Air What is 'Air Conditioning'?Conditioning'?
Air Conditioning is the Air Conditioning is the simultaneous control of simultaneous control of Temperature, Humidity, Motion & Temperature, Humidity, Motion & Purity of the atmosphere in Purity of the atmosphere in confined Space. What are the confined Space. What are the Requirements of comfort Air Requirements of comfort Air Conditioning? Conditioning?
Supply of Oxygen & removal of Supply of Oxygen & removal of Carbon-di-oxide. Carbon-di-oxide.
Removal Of heat dissipated by the Removal Of heat dissipated by the occupants. occupants.
Removal of moisture dissipated by Removal of moisture dissipated by the occupants. the occupants.
To provide sufficient air movement To provide sufficient air movement & air distribution in the confined & air distribution in the confined space. space.
To maintain the purity of air by To maintain the purity of air by removing odor & dust removing odor & dust
What is Air What is Air Conditioning load?Conditioning load? Any heat generated with in Any heat generated with in
the space to be air-the space to be air-conditioned forms a load on conditioned forms a load on the air conditioning system. the air conditioning system.
Examples: Occupants, Examples: Occupants, Lights, Fans, Photocopier, Lights, Fans, Photocopier, Stabilizers, Computers, TV's Stabilizers, Computers, TV's etc.., Heat also enters the etc.., Heat also enters the enclosed space from outside enclosed space from outside through walls, glass through walls, glass windows, roof, open doors, windows, roof, open doors, etc. etc.
What are the types What are the types of Air of Air
Conditioning?Conditioning? Summer Air Conditioning - To Summer Air Conditioning - To
reduce the heat & moisture reduce the heat & moisture Content of the air by cooling Content of the air by cooling De-humidification. De-humidification.
Winter Air Conditioning - To Winter Air Conditioning - To increase the heat & moisture increase the heat & moisture content of air by heating content of air by heating Humidification. Humidification.
Year Round Air Conditioning - Year Round Air Conditioning - To control temperature & To control temperature & moisture content of the air moisture content of the air throughout the year as per throughout the year as per the climatic changes. the climatic changes.
What are the types What are the types of Air Conditioning of Air Conditioning
systems?systems?
Unitary air Conditioning Unitary air Conditioning Systems Systems
Window Air ConditionerWindow Air Conditioner
Split Air Conditioner Split Air Conditioner
Central Air Conditioning Central Air Conditioning Systems Systems
Package Unit Package Unit
Central Plants Central Plants
What do you mean by Ton of What do you mean by Ton of Refrigeration (TR)?Refrigeration (TR)? Ton of Ton of refrigeration is the amount of refrigeration is the amount of heat removed to convert heat removed to convert 1000Kgs of water at ' zero' 1000Kgs of water at ' zero' degrees Celsius into Ice in 24 degrees Celsius into Ice in 24 hrs. In other words. Ton of hrs. In other words. Ton of refrigeration is the capacity refrigeration is the capacity to remove 3000 Kilo Calories to remove 3000 Kilo Calories (12,000 Btu) of heat per hour (12,000 Btu) of heat per hour from the conditioned space.from the conditioned space.
What is BTU?What is BTU? The British The British Thermal Unit (BTU) is defined Thermal Unit (BTU) is defined as the amount of heat as the amount of heat required to raise or lower one required to raise or lower one pound of water to one degree pound of water to one degree Fahrenheit.Fahrenheit.
What is Kilo Calorie? What is Kilo Calorie? It is the It is the amount of heat required to amount of heat required to raise the temperature of 1000 raise the temperature of 1000 grams of water by 1 degree C. grams of water by 1 degree C.
What is Comfort What is Comfort Air-Conditioning?Air-Conditioning?
1. Temperature : 24 + 2 1. Temperature : 24 + 2 Degree Celsius DBT. Degree Celsius DBT.
2. RH : 50 + 10% RH. 2. RH : 50 + 10% RH.
What do you mean by Dry Bulb What do you mean by Dry Bulb Temperature (DBT), Wet Bulb Temperature (DBT), Wet Bulb
Temperature (WBT), and Relative Temperature (WBT), and Relative Humidity (RH)?Humidity (RH)?
1. Dry Bulb Temperature: The 1. Dry Bulb Temperature: The temperature of air measured by temperature of air measured by ordinary thermometer is known as ordinary thermometer is known as Dry Bulb Temperature. Dry Bulb Temperature.
2. Wet Bulb Temperature: The 2. Wet Bulb Temperature: The temperature measured by the temperature measured by the thermometer when its bulb is thermometer when its bulb is covered with Wet Cloth & exposed to covered with Wet Cloth & exposed to airflow is known as Wet Bulb When airflow is known as Wet Bulb When the difference between DBT and the difference between DBT and WBT is Zero, the air becomes fully WBT is Zero, the air becomes fully saturated (100 % RH). saturated (100 % RH).
3. Relative Humidity : The relative 3. Relative Humidity : The relative humidity is defined as the ratio of humidity is defined as the ratio of actual mass of water vapor in a actual mass of water vapor in a given volume to the mass of water given volume to the mass of water vapor if the air is saturated at the vapor if the air is saturated at the same temperature. RH = Mass of same temperature. RH = Mass of the water vapor actually present in a the water vapor actually present in a volume of air at T degree C. Mass of volume of air at T degree C. Mass of the water vapor required to saturate the water vapor required to saturate the same volume of air at T degree C the same volume of air at T degree C . .
What are the basic What are the basic components in an components in an Air Conditioner?Air Conditioner?
1.1. Compressor - It is heart of the air Compressor - It is heart of the air conditioning system. Its function is to suck the conditioning system. Its function is to suck the refrigerant vapor from the evaporator, and to refrigerant vapor from the evaporator, and to raise its temperature & pressure by compression raise its temperature & pressure by compression to a point such that it can be condensed with the to a point such that it can be condensed with the available atmospheric air. available atmospheric air.
2.2.Condenser - The function of condenser is to Condenser - The function of condenser is to provide a heat transfer surface through which provide a heat transfer surface through which heat passes from hot refrigerant vapor to the heat passes from hot refrigerant vapor to the atmospheric air. In condenser high temperature atmospheric air. In condenser high temperature vapor is converted in to high temperature liquid vapor is converted in to high temperature liquid by removal of latent heat .by removal of latent heat .
3.3.Strainer - Strainer is normally fitted in Strainer - Strainer is normally fitted in between a condenser & Capillary tube to remove between a condenser & Capillary tube to remove moisture & foreign particles from the moisture & foreign particles from the refrigerant. The moisture & foreign particles if refrigerant. The moisture & foreign particles if allowed to enter may choke the capillary tube allowed to enter may choke the capillary tube thereby restricting the flow of refrigerant thereby restricting the flow of refrigerant resulting in less cooling / no cooling. resulting in less cooling / no cooling.
4.4.Capillary Tube - It is a tube with a very small Capillary Tube - It is a tube with a very small orifice and its function is to meter the proper orifice and its function is to meter the proper amount of refrigerant to the evaporator and amount of refrigerant to the evaporator and reduce the temperature & pressure of liquid reduce the temperature & pressure of liquid refrigerant entering the evaporator. Hence, this refrigerant entering the evaporator. Hence, this low temperature liquid will vaporize in the low temperature liquid will vaporize in the evaporator and take out sufficient evaporator and take out sufficient amount of heat from room air 5.Evaporator - Its amount of heat from room air 5.Evaporator - Its operation is similar to that of condenser. Here operation is similar to that of condenser. Here Liquid refrigerant is converted to low Liquid refrigerant is converted to low temperature vapor by taking the heat from the temperature vapor by taking the heat from the room air. It is at the evaporator cooling is room air. It is at the evaporator cooling is produced and room is conditionedproduced and room is conditioned
What is What is RefrigerantRefrigerant??
Refrigerant is a substance that Refrigerant is a substance that absorbs heat through expansion or absorbs heat through expansion or vaporization and loses the same vaporization and loses the same through condensation in a through condensation in a refrigeration system.refrigeration system.
In what way refrigerant helps in In what way refrigerant helps in achieving cooling in a confined space?achieving cooling in a confined space?
Refrigerant flowing through the Refrigerant flowing through the closed cycle absorbs heat from the closed cycle absorbs heat from the space to be cooled & rejects heat to space to be cooled & rejects heat to the outside surrounding by the outside surrounding by continuously changing its phase from continuously changing its phase from liquid to vapor & Vice-versa. liquid to vapor & Vice-versa.
Does the use of R-22 affect the ozone Does the use of R-22 affect the ozone layer? layer?
Ozone layer is normally affected by the Ozone layer is normally affected by the presence of chlorine molecules (two presence of chlorine molecules (two atoms) Since R-22 has only one atom atoms) Since R-22 has only one atom of chlorine, the effect of refrigerant on of chlorine, the effect of refrigerant on ozone is very less.ozone is very less.
What is CFM?What is CFM? The Volume flow rate of The Volume flow rate of
air (Volume of air air (Volume of air handled) is measured by handled) is measured by Cubic Feet Per Minute Cubic Feet Per Minute (CFM)(CFM)
What is EER?What is EER?
Energy Efficiency Ratio =Cooling Energy Efficiency Ratio =Cooling Capacity (BTU/Hr.) /Power Capacity (BTU/Hr.) /Power consumption (Watts/Hr.) consumption (Watts/Hr.)
What are the functions What are the functions of various components of various components
used in an air used in an air conditioner?conditioner? Thermostat - Its function is to controls the room Thermostat - Its function is to controls the room
temperature as per the settings by cutting in & off temperature as per the settings by cutting in & off the compressor. the compressor.
Rotary switch - It is through the rotary switch the Rotary switch - It is through the rotary switch the desired mode of operation is selected (i.e.) Off, Fan, desired mode of operation is selected (i.e.) Off, Fan, Super quiet, Normal, High cool etc. Super quiet, Normal, High cool etc.
Running Capacitor - The Function of running Running Capacitor - The Function of running capacitor is to store the current & thereby maintain capacitor is to store the current & thereby maintain constant supply of current to the compressor. constant supply of current to the compressor.
Starting Capacitor - The function of starting Starting Capacitor - The function of starting capacitor is to increase the starting torque of the capacitor is to increase the starting torque of the compressor. compressor.
Starting relay - The function of starting relay is to Starting relay - The function of starting relay is to disconnect the starting capacitor from the circuit as disconnect the starting capacitor from the circuit as soon as the compressor reaches the rated speed. soon as the compressor reaches the rated speed.
Fan Blower - The function of starting relay is to Fan Blower - The function of starting relay is to disconnect the starting capacitor from the circuit as disconnect the starting capacitor from the circuit as soon as the compressor reaches the rated speed. soon as the compressor reaches the rated speed.
Condenser Fan Blade - It sucks the atmospheric air Condenser Fan Blade - It sucks the atmospheric air through sides of the outer cabinet and the same is through sides of the outer cabinet and the same is made to pass through the condenser to take the heat made to pass through the condenser to take the heat from the refrigerant flowing through it. from the refrigerant flowing through it.
Fan Motor - It rotates the condenser fan blade and Fan Motor - It rotates the condenser fan blade and blower for handling the air at condenser and blower for handling the air at condenser and evaporator side. In case of split air conditioner two evaporator side. In case of split air conditioner two fan motors are used. (One at the condensing unit and fan motors are used. (One at the condensing unit and the other at the evaporator unit) the other at the evaporator unit)
Oscillation Motor - This helps to circulate the cold air Oscillation Motor - This helps to circulate the cold air uniformly into the roomuniformly into the room with the help of the with the help of the oscillation louvers. oscillation louvers.
What are types of What are types of compressors compressors
normally used?.normally used?. . Reciprocating Compressor . Reciprocating Compressor
. Rotary Compressor. Rotary Compressor
. Centrifugal compressor . Centrifugal compressor
What types of compressor is What types of compressor is
normally used in Window / Split normally used in Window / Split Air Conditioner?.Air Conditioner?.
. Reciprocating Compressor . Reciprocating Compressor
. Rotary Compressor . Rotary Compressor
پیستونی کمپرسورهای بین پیستونی مقایسه کمپرسورهای بین مقایسهروتاری روتاری و و
RECIPROCATING RECIPROCATING ROTARYROTARY
برگشتی و رفت برگشتی حرکت و رفت حرکتمتراکم را گاز متراکم پیستون را گاز پیستون
..میکندمیکند
غلطک یک دورانی غلطک حرکت یک دورانی حرکتمیکند متراکم را میکند گاز متراکم را . .گاز
سیلندر چند یا تک سیلندر میتواند چند یا تک میتواندشود شود ساخته ..ساخته
ساخته سیلندر تک ساخته فقط سیلندر تک فقط . .میشودمیشود
و خانگی کاربردهای و برای خانگی کاربردهای برایمیشود ساخته تجاری میشود هم ساخته تجاری ..هم
خانگی های کاربرد خانگی برای های کاربرد برایمیشود میشود ساخته ..ساخته
گاز با کمپرسور پیچ گاز سیم با کمپرسور پیچ سیممیشود خنک میشود برگشتی خنک ..برگشتی
گرم گاز معرض در پیچ گرم سیم گاز معرض در پیچ سیمگرفته قرار گرفته دیسشارژ قرار دیسشارژ
..استاست
نباید هرمتیک نوع نباید در هرمتیک نوع دراستفاده مجدد و استفاده تعمیر مجدد و تعمیر
نیمه انواع ولی نیمه گردد انواع ولی گردددر آن باز و در هرمتیک آن باز و هرمتیک
قابل تجاری قابل سیستمهای تجاری سیستمهایاست است تعمیر ..تعمیر
تجدید و تعمیر تجدید قابل و تعمیر قابل . .نیستندنیستند
What is the need for What is the need for having fins in condenser having fins in condenser and evaporator?and evaporator?
Fins are provided to Fins are provided to increase the heat transfer increase the heat transfer area and thereby to area and thereby to improve the efficiency of improve the efficiency of the unitthe unit. .
What is the advantage of What is the advantage of having grooved copper having grooved copper tubes?tubes?
The advantage of grooved The advantage of grooved copper tubes over copper tubes over ordinary tubes is that it ordinary tubes is that it increases the resistance increases the resistance to the flow of refrigerant to the flow of refrigerant and thereby increasing and thereby increasing the heat transfer rate.the heat transfer rate.
Where split air Where split air conditioners can be conditioners can be
installed?installed? 1. It can be installed 1. It can be installed
where window AC's where window AC's cannot be installed. cannot be installed.
2. It can be installed in 2. It can be installed in places where the places where the aesthetics is the first aesthetics is the first priority. priority.
3. It can be installed in 3. It can be installed in places where the noise places where the noise level is to be minimum.level is to be minimum.
Explain how an Air Explain how an Air Conditioner works?Conditioner works?
When the compressor is started it When the compressor is started it sucks the refrigerant vapor at low sucks the refrigerant vapor at low temperature and low pressure from temperature and low pressure from the evaporator through the suction the evaporator through the suction line. After compressing, it discharges line. After compressing, it discharges the refrigerant at high temperature the refrigerant at high temperature and high pressure in vapor state to and high pressure in vapor state to condenser through the discharge line. condenser through the discharge line. Here the vapor is condensed at high Here the vapor is condensed at high pressure by lowering down the pressure by lowering down the temperature of refrigerant with the temperature of refrigerant with the help of atmospheric air, which was help of atmospheric air, which was circulated by condenser fan. This circulated by condenser fan. This liquid flows towards capillary tube liquid flows towards capillary tube through the liquid line & strainer. through the liquid line & strainer. When the liquid passes through the When the liquid passes through the capillary tube, its pressure and capillary tube, its pressure and temperature are lowered and enters temperature are lowered and enters into the evaporator. Here this liquid into the evaporator. Here this liquid refrigerant gets vaporized by refrigerant gets vaporized by absorbing the heat from the room air, absorbing the heat from the room air, which is being sucked by the blower which is being sucked by the blower through the evaporator coil. Hence through the evaporator coil. Hence the room air gets cooled and the same the room air gets cooled and the same is discharged to the room. The is discharged to the room. The compressor sucks the vaporized compressor sucks the vaporized refrigerant at low temperature and refrigerant at low temperature and low pressure. This cycle is repeated low pressure. This cycle is repeated till the compressor works. till the compressor works.
