A motor which is used for circulating the room air through the cooling coil is known as Blower Motor It is fitted behind the cooling coil. It is a fractional horse power motor ranging from 1/4 to 1/5 H P This motor has a double shaft ie the shaft of both sides. At one end a blower is fitted and at other end a fan is fitted to cool the condenser Normally a fin and tube type condenser is used in an air conditioner and split type air conditioner the motor is extended to A Blower Motor is a capacitor run type motor, in which a running capacitor of 4 uF or 6 HF is permanently connected in the motor winding circuit.
OBJECTIVES:
After studying this lesson, you will be able to :
● understand the purpose of a Blower Motor fitted in an air conditioner
● explain the different types of Blower Motor used in an air conditioner
● draw the complete wiring diagram of a two-speed single speed
PURPOSE OF A BLOWER MOTOR IN AN AIR CONDITIONER:
A Blower Motor is fitted behind the cooling coil of an air conditioner and split type air conditioner three speed Blower TONER The cooling coil is usually a fin and tube type. The blower motor is a simple motor with a running capacitor of 4 up or 6 uF permanently connected in its circuit. The Blower Motor has a shaft extended on both side of the rotor It is called double shaft motor At one end of the shaft a Blower and at other end a Fan blade is fitted The Blower side of the Motor is always fitted towards the cooling coil and fan blade side towards the condenser of the air conditioner When Blower Motor is switched ON the Blower sucks the hot air from the room and passes it through the fins of the cooling coil which are at low temperature say 40-45 F. After passing through the cooling coil the air becomes cool and this cold air is circulated in the room and this process is repeated again and again till the Blower Motor is running. So after some time, the temperature in the air-conditioned room becomes comfortable between 70 F to 50 F The direction of flow of this cold air is adjusted with the help of a grill fitted on the cooling coil. Thus the Blower Motor suck the air from the air-conditioned room, passes it through the cooling coil and circulates it evenly in the room with the help of a Blower fitted on the shaft of a Blower Motor.
Types of Blower Motors used in an Air Conditioner
(a) Single speed Blower Motor :
This type of Blower Motor runs at a constant speed hence it is known as single speed Motor It is fitted in an air conditioner for circulating the room air with the help of a Blower which is fixed at one end of the Blower Motor In a single speed Motor four leads are taken out from the stator of the motor for connections.
Types of Blower Motors used in an Air Conditioner (a) Single speed Blower Motor This type of Blower Motor runs at a constant speed hence it is known as single speed Motor It is fitted in an air conditioner for circulating the room air with the help of a Blower which is fixed at one end of the Blower Motor In a single speed Motor four leads are taken out from the stator of the motor for connections.
(b) Two speed Blower Motor:
This type of motor has two-speed low speed and high speed. The speed of this type of motor is selected with the help of a selector switch. In this speed, motor three leads are taken out, and a running capacitor of 4 uF or 6uF is permanently connected in the motor winding circuit.
Rw = Running Winding
Sw = Starting Winding
R = Running Winding Lead
s = Starting Winding Lead
C = Common lead (RS )
H = High Speed
L = Low Speed
Rc = Running Capacitor
(c) Three speed Blower Motor :
This type of Blower Motor has three speeds, Low-Speed Medium speed and High Speed The desired speed is selected with the help of a selector switch.In this type of motor four leads are taken out from the motor and a running capacitor of 4 uF or 6 uF is permanently connected in the motor winding circuit.
WHAT YOU HAVE LEARNT
1. The purpose of a Blower Motor in an air conditioner is to circulate the room air with the help of a Blower fitted at one end of the Motor, A Blower Motor is a simple motor having a shaft extended on both side of the motor, Therefore, it is also known as a double shaft motor
2. There are three types of Blower Motors used in air conditioners Single speed, two speed, and three-speed motor
3. Single Speed Motor runs only at a constant speed It has four leads and running capacitor of 4 uF or 6 uF is connected in these leads and two main leads are taken out for main supply
4. The two-speed motor has two speeds Low and High speed. These speeds are selected with the help of a selector switch. A two-speed motor has three main leads and a running capacitor of 4 uF or 6 uF is permanently connected in the motor winding circuit
5. A three-speed motor has three speeds Low, Medium and High speed It has four main leads and a running capacitor of 4 HF or 6 uF is permanently connected in the motor winding circuit The speed of this type of Motor is also selected by a selector switch
6. Practice each wiring diagram of the blower motor by doing the wiring connections practically to improve your skill.