Choosing the right kit for your home or office can feel a bit like guesswork if you don’t know what you’re looking for. if you are sat there wondering what size air conditioning unit do I need, getting it wrong means you’ll either be shivering while your electric bill shoots through the roof or sitting in a room that’s still sticky and warm. at PAR Refrigeration we’ve been fitting these systems across Yorkshire for over thirty years so we know a thing or two about getting the balance right. it isn’t just about picking the biggest box on the shelf. actually that’s often the worst thing you can do.
Here is the deal on how to figure it all out without getting bogged down in too much technical talk.
What size air conditioning unit do I need for my room?
The first thing you need to look at is the cooling capacity. In the industry we measure this in BTUs which stands for British Thermal Units. Basically it is a measure of how much heat a unit can kick out of a room in an hour. The bigger the number the more powerful the cooling.
If you buy a unit that is too small it’ll just run and run without ever actually making the room cold. It’s a waste of money and it’ll wear the parts out way too fast. However if you go too big the unit will cool the room so fast that it doesn’t have time to actually pull the moisture out of the air. You end up with a room that’s cold but feels damp and clammy. That is why matching the size to your specific space is so important.
For a standard room in a house you can usually do a bit of quick maths. Measure the length and width of your room in feet then multiply them together to get the square footage. Once you have that number you multiply it by 25, that gives you a rough idea of the BTUs you need. Ao a room that is 12ft by 12ft is 144 square feet, multiply that by 25 and you’re looking at about 3,600 BTUs.
However because most fixed units you’ll see in the UK start at around 7,000 or 9,000 BTUs. This is because they’re designed to handle the peak of summer, not just a slightly warm afternoon. For most small bedrooms or home offices a 2.5kW unit which is about 9,000 BTUs is usually the sweet spot.
Factors that change what size air conditioning unit do I need
The basic calculation is a good start but it doesn’t tell the whole story. Every room is different and there are a few things that might mean you need a bit more poke from your system.
Firstly, think about your windows. If you’ve got a south-facing lounge with massive patio doors you’re basically living in a greenhouse when the sun comes out. You’ll need to add about 10% more cooling power to account for that extra solar heat. On the flip side if the room is heavily shaded or north-facing you might be able to get away with a slightly smaller unit.
Then there is the stuff inside the room. Kitchens are the classic example between the oven and the fridge clicking on and off there is a lot of heat being dumped into the air. If you’re putting AC in a kitchen you usually want to add about 4,000 BTUs to your total just to keep up. Even in an office with a couple of big monitors and a server running you’ll notice it gets warmer than a spare bedroom.
Ceiling height matters too. Most guides assume you’ve got standard 8ft ceilings. If you live in an old Yorkshire terrace with high ceilings or a modern barn conversion with a mezzanine there is a lot more air to cool. You’ll need to beef up the unit size to make sure it can actually circulate enough cold air to reach you.
Insulation is another big one. If your house is brand new and holds heat like a thermos you might not need as much power to keep it steady once it’s cool. However if you’re in an older property with draughty windows the cold air is going to escape faster than the unit can make it.
Why it pays to get a professional opinion
At PAR Refrigeration we see a lot of people try to DIY this with portable units they’ve bought online. While they’re alright for a quick fix they aren’t very efficient and the hoses hanging out of windows aren’t exactly great for keeping the heat out.
When we come out to do a site survey we don’t just look at the floor space. We look at the whole building. Our engineers are all F-Gas registered so they know exactly how the refrigerant works and how to get the most out of a split system. We can help you decide between a wall-mounted unit which is the most common or something like a ceiling cassette if you’re doing an office refit.
Getting a pro to look at it means you won’t end up with a system that’s a nightmare to run. We also handle all the maintenance and repairs later on because we’re based in Wakefield and cover everywhere from Leeds to Sheffield we can usually get someone out to you pretty sharpish if things go wrong. We offer 24/7 emergency callouts as well because we know that a broken AC unit in the middle of a heatwave is no joke.
Choosing between different types of systems
Once you know the size you need to pick the style of the AC unit. Split systems are usually the way to go for most people in the UK. You have a sleek unit on the wall inside and a louder compressor unit outside. They’re much quieter than those portable ones because all the noisy bits are on the other side of the wall.
If you’re looking to do multiple rooms you might want a multi-split system. This lets you have one outdoor unit connected to several indoor ones. It’s a great way to save space on the outside of your house while still having individual control over the temperature in each bedroom.
Many of the modern units we fit also act as heat pumps. This means they can actually heat your home in the winter much more efficiently than electric radiators can. It makes the investment feel a lot more worth it when you’re using it all year round, not just for those two weeks of “proper” summer we get.
Final thoughts on sizing
At the end of the day you want a system that you don’t have to think about. It should just sit there and keep you comfortable without making a racket or costing a fortune to run.
If you are still sitting there wondering what size air conditioning unit do I need then just give us a call. We can have a chat about your space and give you a proper quote. You can complete our online contact form or just give the office a ring on 01924 872109. We’re a family-run business and we’ve been doing this since 1986 so you’re in safe hands. Whether it’s a small bedroom or a massive commercial warehouse we’ll make sure you get the right kit for the job.
Don’t let the summer catch you out this year. A bit of planning now means you can enjoy the sun without having to hide in the cellar to stay cool. Give us a shout and we’ll help you get sorted.
