ELECTRICAL SYSTEM OF AIR CONDITIONER

 ELECTRICAL CIRCUIT AND PARTS OF AIR CONDITIONER

In electrical system of air conditioner different types of electrical components are used.The different components of electric system  of air conditioner is given below, that is shown in figure: 

Circuit diagram air conditioner

a) Compressor motor
b) Fan motor
c) Starting capacitor
d) Running capacitor
e) Thermal overload protection
f) Main thermostate or temperature controller
g) Starting relay
h) Unit control switches
e) Fan capacitor
f) Motor compressor units
g) Connecting wire

The detail and working of above electrical components are given below:

1.Compressor motor and fan motor: In air conditioner unit two motors are used.These motors are single phase squirrel cage rotor, type induction motors.

The motor used for compressor motor is mainly capacitor start and capacitor run induction motor and the motor used for evaporator and condenser fan is capacitor start type induction motor.The speed of fan is controlled by induction regulator.

2.Starting capacitor: The starting capacitor provide starting torque to compressor motor and motor starts easily.It is connected to series in circuit.It is generally electrolytic capacitor.

3.Running capacitor: It is purely different from starting capacitor.It is heavy duly oil filled capacitor.It is always connected to series with compressor motor.

It improves the running characteristics of motor and also increases the starting torque of motor.It also increases the power factor, thus current taken by motor decreases (current is inversely proportional to power factor at constant voltage).Thus electrical energy consumption by motor decrease and makes the system economical.

4.Starting relay: This is single phase relay and works on single phase supply.The starting relay coil is always connected in series with running winding of motor.At the time of starting, motor takes high current from supply, thus the contact of relay closed and starting winding of motor and starting capacitor connected with each other and motor starts working.

When the motor speed increase, the value of current in running winding decrease.Thus the contact of relay become open and starting capacitor disconnect from circuit and running capacitor always connected to motor.

The starting relays are two types:

1. Voltage type relay
2. Current type relay

5.Thermal overload protection: This device protect the compressor motor from overloading.So, this is know as overload protection.This is always situated in compressor terminal cover.

When the compressor motor overloaded, current and temperature increase.So at this time if suitable protection is not available motor may be burn.When the motor overloaded the thermal overload protector disconnect the motor from supply and protect the motor.

6.Thermostate or temperature controller: This works on desire room temperature.When the room temperature increases, it closes the compressor circuit and compressor motor starts working.

When the temperature decrease, it break the compressor circuit and compressor motor does not work.Thus it control the room temperature.

7.Unit control switch:This switch is situated at the cabinet.This switch may be knob or rotary type.This switch has four conditions, that is marked by OFF-FAN-COOL-OPEN. 

Conclusion: Thus final conclusion is that, the knowledge of electric circuit diagram and component of air conditioner is necessary.Because it helps at the time of maintenance and repairing of air conditioner.

Important link:

What is air conditioning?Concept of air conditioner

AIR CONDITIONER

 WHAT IS AIR CONDITIONING? CONCEPT OF AIR CONDITIONER (A.C.)?

Air conditioning: Air conditioning means make the atmosphere appropriate.It means in summer it becomes the air cool and in winter it becomes the air hot.

OR

By the controlling of condition of air,make the air suitable and comfortable for human and industry is known as air conditioning.

Factor affecting the comfort of air conditioning:

1.Temperature of air: The temperature of comfort air conditioning room should be 21°C.

2.Humidity of air: The humidity of air of comfort air conditioning room should be below 60% in summer and not more than 40% in winter.

3.Purity of air: The air of comfort conditioning room should be free from dust,smoke,bed smell etc.

4.Motion of air: The motion of air in comfort conditioning should be uniform in desired place.

Function of air conditioning:

1.To control the temperature: It keeps the air cold in summer and hot in winter.

2.To control the humidity: It controls the humidity of air.It keeps the humidity of desired place 50%t to 60%.Thus it prevents from many skin diseases.

3.To clean the air: It cleans (free from dust,smoke,bed smell etc) the air.Thus it prevents from lungs,breath diseases.

4.To control the air flow: It spread the air uniformly at desired place.

PRINCIPAL,CONSTRUCTION AND WORKING OF AIR CONDITIONER:

 Principal: Air conditioning is a process to remove the heat from one area and replaced with cold,pure (free of dust,smoke etc) and uniform air.

Air conditioner

Construction: The main parts of air conditioner is given below:

1. Compressor
2. Condenser coils
3. Expansion valve.
4. Evaporator coils.
5. Fans
6. Connecting pipes.
7. Refrigerant/coolant

Refrigerant/coolant: It is a working substance that transfer the heat from cold body to hot body.The coolant used in air conditioner is mainly FREON gas.In air conditioner it flow through connecting pipes and changes state from liquid to vapour and vapour to liquid.

Working: According to above given diagram.When compressor start working,it compress the coolant gas and increases the temperature of gas.Thus compressor convert the coolant gas in high pressure and high temperature gas.This gas goes to condenser through connecting pipe.

 Condenser Unit

This condenser unit is placed in outdoor means outside of our home.

The heat absorbed by condenser coil to the coolant gas is expelled in atmosphere by the fan that is available in condenser unit.Thus the coolant turns back into liquid at same temperature.

The high temperature and high pressure liquid coolant will leave the condenser and enter the expansion valve through connecting pipe.In expansion valve the pressure and temperature of liquid coolant coming from condenser is decreases.

This low pressure and low temperature liquid enters in evaporator coils.

Evaporator Unit

The evaporator coils are very important to an air conditioner.This evaporator coils is always placed in indoor conditioning unit where the air conditioner picks up the heat from inside our home.The inside hot air blows over the evaporator coils,the cold and de-pressurized liquid coolant absorb the heat from inside home air.Thus by the absorbing inside heat the liquid coolant start vapourize.

Thus the main function of evaporator coil is absorb the heat from inside of our home and it vapourize the liquid coolant that flow inside the evaporator coils.The result of this our home losses heat and starting cools down.

The fan available in evaporator unit circulates the cold air from this coil surface for the cooling effect.

This hot gas/coolant after absorbing heat again goes through the compressor.Thus this process is repeated continuously in a cycle and air conditioner cools our home continuously.

Conclusion: The final conclusion is that air conditioner is a device that remove the heat from an area and replace it with cold air by expelled the hot air in outside the atmosphere.

Important links:

Electrical circuit and parts of air conditioner?