Parts of the Window Air Conditioners: Part One

Windows air conditioners are one of the most widely used types of air conditioners because they are the simplest form of the air conditioning systems. Window air conditioner comprises of the rigid base on which all the parts of the window air conditioner are assembled. The base is assembled inside the casing which is fitted into the wall or the window of the room in which the air conditioner is fitted.

The whole assembly of the window air conditioner can be divided into two compartments: the room side, which is also the cooling side and the outdoor side from where the heat absorbed by the room air is liberated to the atmosphere. The room side and outdoor side are separated from each other by an insulated partition enclosed inside the window air conditioner assembly (refer fig 1 below).

In the front of the window air conditioner on the room side there is beautifully decorated front panel on which the supply and return air grills are fitted (the whole front panel itself is commonly called as front grill). The louvers fitted in the supply air grills are adjustable so as to supply the air in desired direction. There is also one opening in the grill that allows access to the control panel or operating panel in front of the window air conditioner.

The various parts of the window air conditioner can be divided into following categories: the refrigeration system, air circulation system, ventilation system, control system, and the electrical protection system. All these have been discussed in details below along with the front panel and other parts.

The refrigeration system of the window air conditioner comprises of all the important parts of the refrigeration cycle. These include the compressor, condenser, expansion valve and the evaporator. All these components have been shown in fig 3 above. The refrigerant used in most of the window air conditioners is R22.

The compressor used in the window air conditioners is hermetically sealed type, which is portable one. This compressor has long life and it carries long warranty periods. In case of the maintenance problems it can be replaced easily from the company. The condenser is made up of copper tubing and it is cooled by the atmospheric air. The condenser is covered with the fins to enable faster heat transfer rate from it.

The capillary tubing made up of various rounds of the copper coil is used as the expansion valve in the window air conditioners. Just before the capillary there is drier filter that filters the refrigerant and also removes the moisture particles, if present in the refrigerant.

Like condenser, the evaporator is also made up of copper tubing of number of turns and is covered with the fins. The evaporator is also called as the cooling coil since the rooms air passes over it and gets cooled. Just in front of the evaporator there is air filter fitted in the front panel or front grill. As the room air is absorbed, it is first passed over the filter so that it gets filtered. The filtered air is then blown over the cooling coil and the chilled air is passed into the room.

The refrigerant after leaving the cooling coil enters the accumulator where it is accumulated and then it is again sucked by the compressor for recirculation over the whole cycle.

The air circulation system of the window air conditioner comprises of the following parts (please refer fig 4 & 5).

1) Blower: This is the small blower that is fitted behind the evaporator or cooling coil inside the assembly of the window air conditioner system. The blower sucks the air from the room which first passes over the air filter and gets filtered. The air then passes over the cooling coil and gets chilled. The blower then blows this filtered and chilled air, which passes through the supply air compartment inside the window air conditioner assembly. This air is then delivered into the room from the supply air grill of the front panel.

2) Propeller fan or the condenser fan: The condenser fan is the forced draft type of propeller fan that sucks the atmospheric air and blows it over the condenser. The hot refrigerant inside the condenser gives up the heat to the atmospheric air and its temperature reduces.

3) Fan motor: The motor inside the window air conditioner assembly is located between the condenser and the evaporator coil. It has double shaft on one side of which the blower is fitted and on the other side the condenser fan is fitted. This makes the whole assembly of the blower, the condenser fan and the motor highly compact.

1) Book: Basic Refrigeration and Air Condtioning by P N Ananthanarayanan, Tata McGraw-Hill Pubishing Company Limited.

1) H-MAC

2) Visual Merriam-Webster

3) Book: Basic Refrigeration and Air Condtioning by P N Ananthanarayanan, Tata McGraw-Hill Pubishing Company Limited, Second Edition, page no. 213