How To Make A Portable Air Conditioner More Efficient (easy tips)

If you own a portable air conditioner and you’re finding that it doesn’t run as efficiently as it used to, keep reading. Because in this article we will give you all of the information you need to get the best from your portable A/C.

How Does A Portable Air Conditioner Work?

Before we get into how to make your portable aircon run more efficiently, we need to explain how it works. 

By understanding how your A/C works you will have a better understanding why we suggest the actions you need to take to get it running better.

So, let’s quickly run through the way a portable air conditioner works to cool the air in your home:

• Portable A/Cs draw warm air from the room into the unit where some of that heat is absorbed by a refrigerant that is running through a series of looped copper pipes.
• The refrigerant then passes through a compressor which makes it even hotter due to increased pressure.
• It then reaches a condenser where the heat is ejected via the exhaust hose which removes heat from the room. This action lowers the temperature of the refrigerant which becomes even colder once it then flows through an expansion valve.
• At that point the liquid refrigerant turns back into a gaseous state before starting the whole process again.

For more detailed information on how a portable air conditioner works click here.

Ways To Make The Portable A/C More Efficient

Now we know how a portable air conditioner works. Let’s look at ways to make it run better and maximise that cooling process.

Keep The Exhaust Hose Straight

Each individual portable air conditioner will have an exhaust hose of a specific length. The exhaust hose will have been made exactly that length for maximum energy efficiency.

However you can hinder the flow of hot air leaving the unit by allowing twists and kinks in that exhaust hose. The hot air should flow freely from the air conditioner to the outside of your home.

Kinks and twists in the exhaust hose will hinder that smooth journey of hot air. Which, in turn, will make your A/C unit have to work harder to remove that hot air from your home.

Maintain The Exhaust Hose

Just like any twists or kinks can inhibit the flow of hot air from the unit making it work harder. Any splits, tears or leaks in the exhaust hose will allow hot air to re-enter the room.

This will mean the motor has to work to remove the hot air for a second time.

If you do find any splits or tears in the exhaust hose you should ideally replace it with a new one. Or repair it using air conditioner insulation tape which is designed to not lose its adhesive qualities when hot.

Insulate The Exhaust Hose

No matter how straight the exhaust hose is it will still send heat back into the room because it leaks heat. The hose is not thick enough to prevent some of that heat from leaking back into the room.

However, there are insulated hose covers available online which slot over the exhaust hose and help to prevent so much heat loss. You simply slide the cover over the exhaust hose and secure the ends with cable ties.

Choose The Correct Position For Your Portable Air Conditioner

Your portable air conditioner will obviously need to be placed close to a window and a plug socket. But it should also be placed with enough space around it to not hinder air flow.

This means you should allow around a foot (30 cm) at the back of the unit and have nothing in front of it at all. Don’t place any items of furniture etc directly in front of the aircon unit. You should also position it in such a way that the air intakes are not blocked in any way.

You should also keep your portable aircon unit as far away from any direct heat sources like kitchen appliances, TVs etc. If the aircon unit does have to be sited near any of these electrical items, you will need to allow at least 10 feet (3 metres) distance between them.

You might find it’s best to position the unit in a corner of the room and angle it towards the middle of the room. This will give a larger area for the cool air to circulate.

Choose The Correct Model

Portable air conditioners are rated in BTUs (British Thermal Units) and you’ll need the correct rating to get maximum efficiency. Basically 1 BTU is the amount of heat needed to raise ½ litre of water by 1 degree. 

This means the higher the BTU rating your portable air conditioner has, the more likely it is to cool your room efficiently.

So the first thing you need to do is ensure that the portable aircon you buy is big enough for the job, or more importantly the room.

SEE ALSO: Best Portable Air Conditioners (top UK aircon units reviewed)

How To Calculate The BTU Rating You Need

To calculate how many BTUs you will need to cool the room, you’ll need to get your tape measure out. You will need to know the width, length and height of the room in feet.

Then use this simple calculation: width x length x height x 5 = BTU. 

Our room is 15 ft long, 14 ft wide and 7.5 ft high, so we need a portable air conditioner with a BTU rating of at least 7875 because;

15^ft x 14^ft x 7.5^ft x 5 = 7875

Extra Considerations

You then need to think about how many people will be using that room at the same time. This is because people produce heat which means that each person adds to the workload of the aircon.

You will need to allow an extra 1000 BTUs for each person in the room. 

Let’s say that our 15 x 14 x 7.5 room has two people in it, that now means we need a portable air conditioner with a BTU rating of at least 9875 to cool efficiently.

Lower The Settings

If you always run your aircon unit on its highest setting you’re making it run at full pelt all the time. Try using a lower setting because even on a moderate setting your portable air conditioner will cope with high Summer temperatures here in the UK.

You will never achieve sub zero temperatures even at full power. All you need to do is lower the temperature of the room by a few degrees to feel so much cooler when it feels tropical outside.

Keep The Filters Clean

One of the main causes of portable aircons working too hard is clogged filters. The filters work by preventing dust from damaging the internal components of the A/C.

The trouble is that, depending on how much dust there is in the air of your home, those filters can get clogged fast.

It is advisable that you wash the filters every two to four weeks in warm water with some detergent and allow them to dry before replacing them into the unit.

Turn Off All Unnecessary Sources Of Heat

Any electrical device creates a certain amount of heat. From light bulbs to computers to TVs, they all produce heat.

If you don’t need the light on, or if you’re not using the computer or the TV, turn them off. 

It might not seem like it makes much difference but any extra heat will slow down the cooling process of the portable air conditioner.

Cool The Room Before It Gets Too Hot

Obviously, the lower the temperature is in the room, the less work required by the portable air conditioner to keep it cool.

If you know you’re going to need your office for example, for a business meeting at 11 am, get the portable air conditioner set up and running an hour earlier at 10 am. 

This will ensure the aircon is working at a lower rate because it started from a cooler position and now only needs to maintain that cool temperature. 

If you started the aircon unit at 11 am when all of your workforce are in the room, it not only has to contend with the extra heat caused by the additional bodies in the room, but also it’s starting from a hotter time of day and needs to cool further.

Keep Doors And Windows Closed

To run efficiently, your portable air conditioner should only be expected to cool the room that it’s in. Not the adjoining rooms or the outside.

If you leave doors and windows open it will make the aircon have to work harder because it will be contending with hot air from all of those other spaces.

Keep the doors and windows closed in the room that the portable air conditioner is operating in to ensure it only has that room’s heat to deal with.

Seal The Doorways

Even with the doors closed, heat can still seep into a room under the door. To prevent this, roll up a bathroom towel or thin blanket and place it under the door.

If you’re worried about a lack of oxygen, don’t be, blocking the bottom of a door won’t prevent oxygen, just heat.

Pull The Blinds

One of the main ways rooms heat up in the Summer is through sunlight. The sunlight that comes into a room through the windows will make your portable aircon unit work harder.

Sunlight can raise the temperature of a room by anywhere between 10 to 20 degrees.

Pull the window blinds or close the curtains to restrict the amount of sunlight entering the room.

Ensure A Tight Seal For The Exhaust Hose

Most portable air conditioners are supplied with a window kit to allow easy installation of the exhaust hose. However many of these window kits don’t create a tight seal which means they allow hot air back into the room.

Worse still, it’s the same hot air that the unit has just ejected! If your window kit doesn’t fit correctly you will need to address this issue. If you can see gaps around the edges try taping them up.

If necessary fashion your own window kit using plywood or polystyrene and ensure it fits tightly and seals the gaps fully.

Drain The Water Tank

Most portable air conditioners have auto-evaporation systems which remove any moisture that forms on the evaporator. But some still have a water tank which collects that moisture.

If your unit has a water tank, it will need emptying regularly to keep the unit running efficiently.

Get A Newer Model Aircon

If you’ve owned your portable air conditioner for a few years, it might be a good idea to upgrade to a newer model. Older units tend to not be as energy efficient as more up to date models.

This is sometimes due to the compressor not running as well as it was designed to when new. This can not only decrease the efficiency of the unit, it can also cause more heat due to increased friction inside the components of the unit.

Experts recommend replacing a portable air conditioner every 5 to 8 years if you want to reduce running costs and noise levels too.

Ensure You Store Your Portable A/C Correctly

When Summer ends, you’ll need to ensure that your portable aircon unit is stored away correctly if you want it to work efficiently next year.

This entails draining the water tank and switching the unit on to fan mode for a few hours. This will completely dry the unit making it safe to store away.

You should then clean and dry the filter, replace the portable air conditioner in its original box etc and store in a dry location.

Allow Cool Air Into The Room

Early in the morning take advantage of that early morning fresh, cool air by opening the window. This allows the room to cool naturally before the day heats up. 

Then as soon as outside temperatures start heating up, close the windows and turn on the portable air conditioner.

This means the aircon doesn’t have to work so hard to get the room to your desired level.

Structural Intervention

We know that in most cases this is a step too far, but this article wouldn’t be complete if we never mentioned the following. In many cases a draughty home is the cause of most energy inefficiency in portable air conditioners.

Ill fitting doors, windows, single glazed windows, etc are all reasons why aircon units have to work so hard.

Obviously replacing doors and windows can be expensive and a lot of trouble. However, you can use weather stripping or sealant to reduce draughts.

Even adding thick curtains can curtail those unwanted draughts.

Choose A More Efficient Unit

Portable air conditioners all work on a similar principle, but some are designed to be more energy efficient than others. For instance dual hose units are far more energy efficient than single hose units.

This is because a single hose unit relies on the air in the room to cool the components down. Whereas a dual hose unit actually draws air in from outdoors to cool the internal working parts down.

Sadly, these dual hose models are few and far between and if you are fortunate enough to find one, they are usually more expensive. Plus they take longer to install because you need to fit two hoses to the window kit.

Look For Eco-Settings

There are several portable air conditioners which have eco-settings which allow you to operate your unit more efficiently. This can help to get a cooler living space without paying too hefty a price for electricity.

SEE ALSO: How Much Does It Cost To Run A Portable Air Conditioner? (UK prices)

Frequently Asked Questions