Air conditioning requirements across the world are increasing at a significant rate. An increase in temperature, heatwaves, and unpredictable weather is one driver for the high demand. An increase in energy efficiency and affordability is the primary demand driver. Individual requirements vary extensively, and manufacturers are innovating rapidly.
To cater to the varied requirements of home-owners, the manufacturers have made available a wide variety of air conditioners.
Common Air Conditioning Systems
For homes, the following are the most prevalent types of air conditioners
- Window AC
- Single Split Ductless AC
- Multiple Split Ductless AC
- Cassette AC
- Ducted AC system
- Portable AC
- Floor Standing AC, and
- Central Air Conditioning
We shall now proceed to compare the individual aircon systems and uncover how they are different from their counterparts.
Air conditioning systems – Deep dive
For an average home, the choice of an air conditioner depends on budget, ease of installation, area of the house, portability requirement, and certain other factors that we shall cover in the individual sections.
1. Window Air Conditioner
The Window AC derives its name from where it gets installed – on a window. Buying an AC is a decision often taken much later than the construction of the house. Aircons need space. During construction, there may not be a planned space dedicated to AC fitment.
The most comfortable choice is window aircon. It is often the simplest and among the cheapest air conditioners available. The window AC is a single unit that needs to be secured to the window. The only separate part in a window AC box is the remote controller.
Installation is easy compared to other aircons. The unit needs to be slide across the window opening and secured to the window or wall. There may be a size difference between the AC unit and the window. That excess needs to be closed. It is closed using heat-insulating materials like wood. Aircon service for these types of aircon is very easy, provided there is enough space in the room to dismantle and clean is.
- The window AC is a compact single unit and does not require complicated installation
- After installation, all you need is a power socket
- Cost-effective – Often the cheapest when compared to other kinds of ACs of the same capacity
- Capacity – Typically available from 0.75 tons (9000 BTU/hour) to 2 tons (24000 BTU/hour)
- Low capacity AC availability for tiny rooms
- Easier and cheaper maintenance. Dismantling for transport is very easy.
- No loss of refrigerant during transport
- Aircon servicing is relatively easy
2. Single Split Ductless Air Conditioner
The split ductless AC is the most popular variant opted by households. The AC is “split” into two components – the indoor unit and outdoor unit.
The outdoor unit (ODU) is the condenser unit that contains the compressor and a heat exchanging coil. It is mounted outside the house premises. The outdoor unit needs to be in the open air to function correctly. It can be installed on the wall or attached to the ground.
The indoor unit (IDU) has a coil that cools down and extracts heat from your room. The indoor unit is wall-mounted at the height of at least 8-9 feet from the floor. This ensures that it does not consume usage space in your room.
The indoor and outdoor units are connected through pipes that carry the refrigerant. The installation comprises mounting the indoor and outdoor units and connecting the pipes. Once the technicians confirm that the units have been installed correctly, they fill refrigerant in the system.
Manufacturers provide a long list of features – horizontal and vertical swing, sleep tracking, automatic temperature adjustment (often called comfort mode), mosquito repellant system, air filtering systems, and many more. Today’s smart split AC comes with built-in Wi-Fi and can be controlled using a mobile phone or a smart assistant like Alexa or Google Home.
Heat-Pump: There are split units that have both cooling and heating facility. Since the AC is a heat pump, if the flow is reversed, the indoor unit acts as a heater. Such dual-purpose units serve well in areas that have extreme temperatures throughout the year. . Aircon service for these types of aircon is moderatly easy, provided there is access to the compressor unit.
- The split AC has two units and a pipe system
- Installation is relatively complicated – drilling holes to setup pipes, setting the wastewater drain pipe
- Cost– Initial cost is higher than window aircons
- Split AC does not consume the floor area
- Capacity – Typically available from 1 ton (12000 BTU/hour) to 3 tons (36000 BTU/hour)
- High capacity split AC can effectively cool a large hall
- Available with fancy features
- The maintenance requirement is higher than window AC
- Complete loss of refrigerant during transport
- Aircon servicing complexity depends on the location of the compressor
3. Multiple Split Ductless Air Conditioner
It is like the single split AC in all aspects except that it has one condenser unit driving all the indoor units. Indoor units of different capacities can be used in different rooms as per the cooling requirement.
The condenser unit consumes energy according to the number of indoor units switched ON and their temperature setting.
The multiple split system negates the need for having a separate outdoor unit for every indoor unit. This reduces space requirements and saves on cost.
The ductless multi-split AC system can start from a two-unit (two indoor units) system. Bigger models can support up to five units.
Home users should plan the construction or renovation of their housekeeping into consideration the fixture points and piping requirements if they intend to have a multi-split AC system installed. . Aircon service for these types of aircon is very easy, provided there is enough space in the room to dismantle and clean is.
- Cost– Lower cost when compared to single split AC for every individual room
- Lower floor area requirement to mount the outdoor unit
- Capacity – The capacity of the condenser depends on how many units it supports and their respective tonnage
- Better energy efficiency due to a shared outdoor unit
- Single point of failure – if the outdoor unit fails, the system stops functioning. This contrasts with single split ACs where one aircon is independent of the other
- Aircon servicing is little complex and depends on the location and design.
4. Cassette Air Conditioner
The cassette AC is meant for installation on a false ceiling. It is like the split AC when the number of parts is compared. This system also uses a set of pipes to carry the refrigerant from the condenser unit to the cassette unit mounted on the ceiling.
The cassette is a thin unit and can be used in narrow spaces that would be obstructed if fitted with a wall-mounted split unit.
This AC is also suitable for areas that have very high ceilings. Cassette aircons have four-way airflow, and cooling is more uniform than other aircons discussed so far. In the case of a high ceiling, the cassette AC is superior to other forms. Heat rises up and is extracted by the cassette unit. The four-way airflow provides a consistent temperature throughout the premises.
- Cost– Cassette AC unit is higher priced than a split ductless aircon
- Fits on a false ceiling. No floor or wall area is required
- Capacity – Cassette ACs start from a higher capacity when compared to window or split units. Most manufacturers have cassette units starting from 2.5 ton or 3 ton.
- Suitable for large halls where a split AC cannot provide uniform cooling
- Ideal for high ceiling
- Less draft (airflow) is felt when using a cassette AC
- Suitable for halls where wall mounted units would affect the aesthetics of the premises
- Aircon service depands on the height of the cassette and enough room.
5. Ducted AC system
Ducted Air Conditioners are used more often at offices than they’re used at homes. There is a central cooling/heating unit, and a network of ducts passes through false ceilings. The ducts vent to the rooms.
Every room has its own thermostat, which allows for different temperature “zones” to be created on the premises. The flow of conditioned air is stopped when the set temperature is reached.
Ducted AC systems appear to be seamlessly integrated with the home or office. It is better to plan for a ducted system when the structure is being built or renovated.
A big area is required to keep the cooling unit/furnace, and the network of ducts requires careful planning. The vents inside the rooms look better if planned rather than a retrofit.
- Cost– Ducted AC systems are expensive because of their scale but cost less when compared to individual units
- Ducts and vents need careful planning. If planned well, the AC is seamlessly integrated with the room
- Capacity needs to be planned before buying the unit. Since the furnace/cooling system is fixed, changes in capacity could be hard to achieve
- Ducted AC systems have individual thermostats for each room
- These systems allow “temperature” zones to be created whereby different requirements can be addressed simultaneously
- Retrofitting a ducted system may be expensive and require a considerable installation time
- Aircon servicing is complex for these systems.
6. Portable AC
This is an incredible innovation in the field of air conditioning. The portable AC is a standalone unit, having dimensions less than a small washing machine. It has caster wheels that allow it to be moved.
This is a useful appliance for those who move frequently or live in rented accommodation where they are not allowed to modify the premises in any way. These portable units have a durable pipe (thick as a hose) that vents off the hot air. This hose needs to be secured to a window with an airtight attachment. Manufacturers provide various window sealing attachments that work for most windows.
Portable ACs are useful for those who want cooling in different rooms but are on a budget. The AC can be used in all those rooms where the window hose fixture is attached.
These ACs may cost higher than split units and may not be available over 1.5- or 2-ton capacity.
- Easy installation, Do-It-Yourself (DIY) isn’t hard either
- Ideal for rented accommodation. Most other forms of ACs require changes to the window, wall, or ceiling
- One unit can serve multiple rooms (not simultaneously)
- Easy to transport
- Repair charges are lesser due to ease of transportation
- No mounting or dismounting required
- Aircon servicing of this type is relatively easy, but the time taken to unscrew the equipment will take time.
7. Floor Standing Air Conditioner
A floor standing air conditioner is another type of split air conditioner with the difference that the indoor unit is kept on the floor. The other aspects remain the same. There is a refrigerant pipe that connects to a condenser unit outside the premises.
The floor-standing AC is typically available in higher capacities than split ductless wall mounted aircons. The standing ACs are ideal for large halls that the glass windows. The glass allows heat to be trapped inside the premises.
Since the source of heat is located at one corner of the hall, floor standing air conditioners do a better job of maintaining a uniform temperature inside. They trap the heat at the source and vent it off to the atmosphere.
Floor standing units are expensive because they typically have a capacity higher than 3 tons. Multiple fans add to the cost. However, considering the benefits of a floor standing AC, the pros outweigh the cons.
- Installation is similar to a split AC except for the indoor floor standing unit
- Ideal for halls or rooms where there is a significant source of heat in one corner
- High cooling capacity
- The indoor unit may be slightly moveable if the pipes are flexible
- Wall or ceiling mount isn’t required
- People living in rented accommodation can use this without requiring significant changes to the structure of the premises
- Aircon servicing of this type is relatively easy, but the time taken to unscrew the equipment will take time
8. Central Air Conditioning
This is the most sophisticated form of air conditioning available for the home. The core cooling/heating unit is placed at one location. From that unit, a network of pipes and ducts originates that supply air to the rooms.
The central air conditioning system has a set of condenser units that provide the required heat exchange.
Air Handling Unit (AHU) – You may have heard this phrase before. The air handling unit is the furnace where the air is conditioned for temperature and humidity. It is then circulated through the ducts to the rooms. The central air conditioner typically provides both cooling and heating features.
Since the central AC is meant to cool the entire house, the capacity of the central AC system is based on the square feet area that needs cooling. Based on the climate, there are reference numbers for the cooling capacity (BTU per hour per square feet, tons per thousand square feet, kW per thousand square feet). It is advisable to have a system with some buffer capacity (15-20% higher than calculated) to take care of the efficiency decrease over time.
Digital or rotary thermostats are provided in each room for room-specific temperature control. This helps in the formation of temperature “zones” in the house, based on the temperature requirement of the occupants of the room.
Structural Decisions – It is feasible to go for a central air conditioning system since there are a lot of structural considerations that need to be addressed so that a central AC can be integrated with the house.
If you plan to get a new house constructed, inform your designer that you want a central air conditioning system installed. Multiple factors must be considered – placement of the furnace, ductwork, air vents inside rooms, electrical considerations, and a lot of other factors.
- Installation feasible when the house is being constructed or renovated
- A lot of design consideration comes into the picture
- The entire premises are air-conditioned
- Temperature zones can be created to cater to individual comfort requirements
- Higher efficiency than different units installed in every room
- Consider this if you want a seamless AC system in your home
- AC servicing of this type is relatively complex, and need to study all the designs to understand the equipment schedule
We hope you have enjoyed reading about the different types of air conditioners available. We’ve marked the noteworthy points for quick reference. Air-conditioning systems differ in many ways. Individual requirements must be considered before making a purchase decision. For information on capacity, efficiency, and other aspects, there is a set of exciting blog posts. We believe you should be making a well-researched and informed decision. MCL, a Singapore based aircon servicing company can be relied on for any aircon servicing needs.