Portable Air Conditioners, Air Coolers and Fans
Summer 2022 had record temperatures and the MET office is predicting an even hotter summer for 2023 so here are our tips on keeping cool, with advice on buying and using fans, air coolers and portable air conditioners.
Take a look at our post on Keeping Cool This Summer for low budget ways to beat the heat, yes they work, I've tried them and I will be using them again this year.
If you are looking for appliances to help you 'beat the heat', then here's the guide.
- Use a Fan:
If you want the feeling of air blowing over you or need to keep circulating air around a room. Skip to About Fans
- Use an Air Cooler:
If you want cool air for a short while and are not fussed about wet (humid) air, or need to humidify your room (e.g:- if you are in a dry climate). Skip to About Air coolers
- Use an Air Conditioner:
If you want to keep a room at a constant cool temperature, clean the air and are not fussed about dry air or need to dehumidify your room (e.g:- if you are in a wet climate). Skip to About Air Conditioners
A fan blows air around, it does not cool air down. The fan motor generates heat while working so it actually heats the air up a little.
Your body cools itself by sweating, as the moisture evaporates it takes heat away from your body
A fan cools your body down by blowing air over your skin causing sweat to evaporate more quickly.
Fans do not clean the air or change its moisture content, if it's a hot humid day they blow hot wet air around. If it's a hot dusty day they blow hot dusty air around.
Fans are cheap to buy, they are useful for:
Freshening rooms by moving air around without the need for cooling, cleaning or changing the airs moisture content.
Venting rooms, dispersing odours or water vapour, a bathroom extraction fan is a good example of this.
This fan circulates air around a greenhouse
If you want to cool air then you need an air cooler or a portable air conditioning unit.
There are a huge variety of styles and sizes, from very small personal desk fans which drive air a single person to giant pedestal fans which push air through an entire room.
A small personal fan
Use a slowly rotating large-diameter fan for circulating air around a room, a speedy smaller-diameter fan will give faster-directed airflow.
You can even buy pocket-sized battery-powered fans like this one to keep you cool on the move.
» Read full review
This is a good quality robust and compact lightweight personal mini fan with a 4-inch (10.1cm) blade, it’s light enough to clip to your laptop while working ( do not clip onto the screen! )
The fan is made from sturdy ABS plastic, making it shock resistant and has a good strong clip for attaching it, the clip is flat bottomed so it can be used as a stand up fan as well.
There is a brush-less motor for quiet (but not totally silent) running, our test model measured <40dBA at one meter and we couldn’t hear it over normal office conversation
It can be powered from any personal device with a USB output, PC, Laptop, Playbook Mac etc… or used with a mains adapter
While there are cheaper personal fans available, we really like this one and have had such great feedback that we have to recommend this as one of the best. Of 500 verified users 82% have given it a 5 star rating with the other 18% giving it 4 stars.
Dimensions: Height 20.1 cm Length 20.1 cm Depth 9.9cm. Weight 220 grams. Voltage 5v. Max power 3.5w
Supplied with a 1.5 meter USB cable
Available in Black, White Pink or blue (prices vary with color)
» Read less
Directed flow fans channel a stream of fast-moving air towards a particular spot. Oscillating fans swing from side to side blowing air towards every corner of a room. Take a look at a range of Fans on Amazon
Before choosing a fan, decide what it is you want it to do, then choose from those designed for that purpose.
Check the manufacturer's warranty and customer reviews before you buy.
For desk or pedestal fans, we recommend VonHaus, they are reasonably priced and have 2-year guarantees.
Dyson Tower Fans
They are fans, very clever fans with a brilliant air purifying system, but they are not air coolers or air conditioning units. Like all fans, they push air around but do not actually cool it.
Air coolers also humidify (add moisture to) the air because the water evaporates as the air passes through the machine.
They will cool the room but only as long as the water in them is cold.
- We've tested many domestic air coolers, and the only positive thing we found with them is they do not dry out the air.
- Noisy and inefficient, the cheaper models are unreliable and break down frequently.
- Most of them leak, especially when moved, as they are full of water.
- Reliable ones are expensive, cheap ones are not worth buying.
The average domestic user would be better off using a fan and a bowl of ice. As shown in our article 7 Cheap & Easy Ways To Keep Cool This Summer.
If you need moist air and must have an air cooler we haven't found a domstic one we can recommend, we suggest you have a look at Air Coolers on Amazon, and carefully read the reviews before buying one
The bigger & more powerful the fan the greater the airflow, the larger the reservoir the longer it will keep the room cool.
Also, look out for multiple speed settings, air coolers don't have thermostats so you control the airflow with the fan speed.
Our recommended best-buy air cooler is the commercial-grade Honeywell CL48PM. At £330 it is pricey but this is a model that works efficiently year after year. It has a 48-litre tank and can be plumbed directly into the mains water supply. It is one of the best-selling air coolers in the world It is designed for function and is quite noisy,
An air cooler is a cheap substitute for an air conditioner, why not get a portable air conditioner instead?
These come in two types (if you want to know how they work look here)
Fixed air conditioning units:
They draw in air from outside cooling it using a heat exchanger set outside of the building before blowing it into the room.
The vents for airflow are fixed in windows or walls.
Portable air conditioning units:
These are compact portable appliances which suck air from the room into the unit which contains a heat exchanger.
They draw heat out of the air and a fan then blows the cooled air back into the room. The hot air is exhausted out of a ducting hose which is usually hung out of a window.
Air conditioning units purify and dehumidify (remove the moisture from ) air passing through them, filtering out dust and blowing out cool, clean, dry air.
They all come with thermostatic controls to keep the room at a constant temperature and, like heaters, there are a range of extra options you can have depending on your needs.
Air conditioners were originally designed to remove moisture from the air and will dry out air in the room, they also need an external vent to get rid of waste heat (usually a flexible ducting hose).
Portable ones can be moved from room to room, in heatwaves you can use it in the lounge during the day and in the bedroom on those hot sultry nights.
During winter they can be used as dehumidifiers to remove dampness from the air, preventing mould, mildew and condensation problems.
Some have a heating function which you can use for all-year-round climate control.
Choosing a portable air conditioner
A too-small unit will burn excess energy as it will overwork to keep your room cool, and a too-large unit will keep switching on and off too quickly, either way, they will cost you more to run than the right-sized air conditioner for your space.
In the UK Air conditioners are usually rated in British Thermal Units (BTUs) 1 kW = 3,400 BTUs
Roughly calculated you will need about 30 watts (115 BTUs) for each cubic meter ( m3 ) of space.
We advise buying an air conditioner with a minimum output 7000 BTUs this is the minimum required to cool a small room (40m3) on a hot day.
Larger rooms up to 60m3 need around 10,000 BTUs and open plan rooms, lofts and office spaces up to 90m3 need at least 15000 BTUs.
Choose the right size for your room, then select the extra controls for your needs (remote control, timer etc...)
To see a range of options please visit our award-winning partners, the air conditioning experts at Airconcentre
Tip: If you have issues with dry air then a bowl of water placed across the room from your air conditioner and topped up regularly will keep the air moist.
Air conditioning units were originally designed as dehumidifiers to remove moisture from the air to keep paper stock at a publishing company dry during humid summers.
Because cold air holds less moisture than warm air the warm moist air was cooled by blowing it across cold pipes. The cooled water condensed out of the air drying it, cooling the air was a fortunate side effect of the process.
An air conditioner does this by refrigerating the air using a technique known as phase conversion, this is a law of physics which states that when a liquid changes to a gas it absorbs heat, so air conditioners use a closed system of coils containing chemicals called refrigerants which constantly change from gas to liquid and back again.
When the fan blows warm air from the room over one set of coils (evaporator coils) the refrigerant changes from a liquid to a gas absorbing heat from the air, this cold air is channelled into the room cooling it.
The gas is then pumped into a compressor which pressurizes it causing it to turn back into a liquid. This now warm liquid flows through a second set of coils (condenser coils) and a second fan blows over these coils removing the warm air (which is channelled outside) and cooling the liquid, which is then routed back to the evaporator coils and the process starts all over again.
With portable air conditioning units, the hot air is vented out via a ducted hose which can be hung out of a window or attached to a wall vent, similar to the way a tumble dryer is vented.
For more info on buying and using air conditioners see the Air conditioner buying guide at aircon centre