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Air conditioning: everything you need to know

Ever wondered how air conditioning works? Discover our helpful guide to learn more above types of air conditioning, how they work and installation costs.

In the UK, air conditioning can be seen as a luxury reserved for the wealthy and business owners, but this isn’t the case. With summer temperatures affecting our sleep and working from home becoming more prominent, now is a great time to invest in an air conditioning unit.

This guide will cover areas such as what is air conditioning, how does air conditioning work and the different types of air conditioning units. Plus, we will also help to give you a rough idea of the cost of installing air conditioning in your home.

What is air conditioning?

You may have a rough idea about what air conditioning is but not actually how it works or even what a unit looks like. That is why many people still ask what is air conditioning? Generally, air conditioners use a refrigerant to take heat from a room and cool the air, unlike electric fans that just move air around the room, not cooling it at all.

As such, air conditioners are usually much more expensive than electric fans but are far more effective at cooling a room. There are many different types of air conditioning systems available including portable or monoblock air conditioners and split-unit air conditioners.

The main difference between the two is that monoblock air conditioners can be plugged into a power socket in any location, and split-unit air conditioners are fixed in place.

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How does air conditioning work?Installing air conditioning

Air conditioners are the perfect way to stay cool during hot weather, but you may be wondering how does air conditioning work? Below we have summarised the process by which air conditioners cool the air in your home:

1) An evaporator coil absorbs the heat

The air conditioner’s vent draws in any warm air which passes over a cold evaporator coil inside the home. This absorbs the heat and in turn, cools it. The resulting cool air is passed back through air ducts into the home.

2) Refrigerant temperature is raised

Next, the gas is tightly squeezed between two solid objects in the air conditioner’s compressor. As a result, the refrigerant’s temperature and pressure are raised, turning it into a superheated vapour. This vapour is then passed through the condenser where it reaches the outside air and is turned back from a gas into a liquid.

3) The refrigerant temperature lowers

The cycle then continues anew, with any heat from the refrigerant returning to the evaporator. If your home is not yet at the desired temperature then this process will continue until it is reached.

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Air conditioning for flatsTypes of air conditioning unit

With a wide range of air conditioners to choose from, it is important to pick the best unit for your requirements. You will also need to choose the right capacity air conditioner for your home if you want it to be fixed in place, and whether you want it to cool one area or your entire house.

Depending on your needs, it may be easier to choose a portable air conditioner that can be transported to wherever you require it or to simply have it permanently in a particular room. Fixed air conditioners can be mounted on your wall, floor or window. You can also choose an air conditioning unit with extra features, such as:

  • Dehumidifier function
  • Multiple fan speeds
  • Remote control
  • Timer
  • Night mode/noise reduction
  • Heating mode

Below are the two main types of air conditioning unit:

Monoblock air conditioners

These are also known as single-unit, standalone or portable air conditioners. They plug into a mains power socket with a hose dangled outside from a window or door. This system does mean that there must be an open window/door to vent the hot air from.

They are not ideal for those who suffer from hayfever, and there will be some hot air that will come back into the property, making them less effective than fixed air conditioners. Although, it is possible to buy a window sealing kit to block off the window gap.

This type of air conditioning unit is generally cheaper than split-unit air conditioners. They are easy to use as there is no installation required and being portable, they can be moved to the area where they are needed most.

Monoblock air conditioners are a great solution for the UK, as generally the climate does not require cooling for more than three months a year. In cooler months the unit can be stored away, although they can be heavy to move.

Split air conditioners

These are also known as fixed air conditioners. They are comprised of an indoor unit (fixed to the inside of an exterior wall) and an outdoor unit (fixed on the other side of the wall or installed on the ground outside). This is a great solution for a room that consistently gets very hot.

Split air conditioners are a fixed unit, so cannot be moved to other rooms, or stored when the warmer months end. They are permanent fixtures and will need to be installed by a professional.

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Modern room with air conditioningWhat size air conditioner do I need?

Once you have decided that an air conditioner is the perfect option for you, you may be asking ‘but what size air conditioner do I need?’ This will mostly depend on the size of your home/room and whether you want to cool one space or the entire property. The larger the area you wish to cool, the larger the air conditioner you will need.

Air conditioners are often described in terms of their BTU (British thermal unit) output. The higher the BTU, the more efficiently it will cool a room. In most cases, 5,000 to 8,000 BTUs is enough for most living rooms or bedrooms.

To work out what BTU is right for you, as a very rough guide, multiply the dimensions (in feet) of the room by five. So, for a room measuring 15 by 10 by 8 feet: 15 x 10 x 8 x 5 = an air conditioner of 6,000 BTUs.

How much does air conditioning cost to be installed by a professional?

The two main types of air conditioner (monoblock and split) are very different when it comes to installation cost, difficultly and time. Monoblock air conditioners need very little in the way of fitting where split unit air conditioners require extensive work to fit. Below is a rough guideline of what you can expect to pay:

Split-unit air con: 

  • For one room- £1,500 – £2,500
  • For a house/six rooms – £5,000 – £9,500

Portable unit:

  • £200 – £900 per unit

If you need to know more about professional air conditioning fitting, why not check out our air conditioner installation cost guide for more prices, tips and considerations.

What next?

Investing in air conditioning for your property can keep you cool on the hottest of days and help to aid sleep no matter the outside temperature.

If you have decided an air conditioning unit is the perfect solution to your summer discomfort, please use our free search feature to find a range of trusted professionals in your area who would be happy to help.

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