An AC unit with too high of a BTU rating will cycle on and off more frequently, eventually cooling your space excessively. On the other hand, AC units with too few BTUs will need to run constantly to reach the target temperature, which may add strain to the system.
An air conditioner with BTUs that exceed the recommended square footage in your home may also take on more wear and tear over time because it will initiate its on/off cycle more frequently. It could also create a subpar cooling experience because your AC's compressor may turn off much sooner than it should.
The cooling capacity should be equal to or higher than the heat gained and heat generated. That depends on the outdoor temp, humidity, sunshine, windows, number of occupants, activities in the room, fresh air change, wall material and equipment in the room. A rough estimate would be around 12000BTU per room.
BTU is a climate capacity unit. The abbreviation means “British thermal units.” It is estimated that an air conditioner with a capacity of 9000 BTU is sufficient for a room of 20 to 35 square meters. For a room of 35-60 square meters – you need air conditioning capacity of 12000 BTU.
There is a recommended BTU By Room Size. If you have a room size of 10'x 20' (200 square feet), you 'will have to look at a 6000 BTU as a unit. Once you get into 340 square feet and 400 square feet range per room, you would need an 8000 or 9000 BTU air conditioner, for this space respectively.
So a higher BTU than needed is definitely not recommended. Installing an air conditioner that is too small for the space is also not recommended, since it will run continuously. It will not be powerful enough to cool the space adequately.
You'll need to know your room size too. In general, a 5,000 to 6,000 BTU air conditioner can cool between 100 and 300 square feet. Seven thousand to 8,200 BTU units are adequate for cooling 250 to 550 square feet, while 9,800 to 12,500 BTU models cool up to 950 square feet.
Simply choosing the highest BTU-rated unit may result in inefficient cooling and increased energy consumption. An AC unit with too high of a BTU rating will cycle on and off more frequently, eventually cooling your space excessively.
As a general rule we advise you to buy an Air Conditioner with a minimum 7000BTUs as this is the minimum required to call a small room (18sq/m) on a hot day. Medium rooms (24sq/m) need around 10,000BTUs and larger rooms and office spaces (36sq/m) require around 15000BTUs.
BTUs measure the energy output of your AC system. It takes about 20 to 35 BTUs to cool each square foot of space. Higher BTUs cool a room faster, but boost humidity and wear your unit down.
So, yes, you absolutely can oversize a minisplit. And when you do, you end up with some of the same problems you get from oversizing conventional systems: comfort problems, poor humidity control, short cycling, and wasted money.
As a general rule, the recommendation for an average double bedroom is a 9,000BTU air conditioning unit. 'BTU' stands for British Thermal Unit and is a unit most commonly used to measure energy when they're discussing machines that heat or cool air – such as air conditioning units and heaters.
Whether you are talking about an air conditioner or a heating device, you will often also see a mention of BTUs per hour which directly correlates to a kilowatt-hour in terms of energy usage. More BTUs produced per hour will generally cost more in terms of electricity usage compared to a device with a lower BTU output.
Higher Utility Bills
A bigger unit simply gobbles more power than a smaller one. To make matters worse, your oversized air conditioner will likely never reach its promised level of energy efficiency. Just as it is cycling up to its most efficient level, the thermostat will tell it to shut off again.
First, if the system is too small for the space it is intended to cool, there may be inadequate cooling and an inability to maintain a comfortable temperature. This could result in overworked components due to the excessive strain on the system, leading to higher energy costs and a shortened lifespan of the unit.
Neither oversizing nor undersizing your AC unit is ideal. Both scenarios can lead to issues with efficiency, comfort, and longevity of the system.
If your space is 300 square feet, you want to find a model capable of producing at least 6,000 BTUs. As a guide, consider 5,000-BTU models for rooms 150 square feet or smaller, 8,000 BTUs for medium-size rooms (340 square feet), and 12,000 to 14,000-BTU models for rooms with square footage from 550 to 800.
More is not better. A unit with too many BTU's, will cool the room fast, but leave the room humid. Too few BTU's will never cool the room down and the unit will run incessantly. To be sure you're making the right decision, call us to get answers about air conditioner sizes and efficiency.
A 5 star AC offers superior energy efficiency, leading to lower electricity bills, while a 3 star AC is more budget-friendly but tends to consume slightly more power. If you're undecided on whether to go for a 5 star or 3 star AC, consider factors like long-term energy savings and initial costs.
Selecting the right sized unit is key to comfort and savings. Remember, bigger is not always better. —An over sized air conditioner will be less effective. Air conditioners remove both heat and humidity from the air, but if the unit is too large, it will cool the room, before it has a chance to remove the humidity.
For common flat bedrooms, a 6,500 BTU air conditioner will do its job. A BTU of up to 9,000 is needed for dedicated home offices to prevent overheating your computer and other electrical office equipment.
Homes measuring 1,000-1,500 square feet: You'll need a 2-ton unit, which corresponds to a cooling capacity of 24,000 BTUs per hour. Homes measuring 1,500-2,000 square feet: You'll require a 3-ton unit, equivalent to 36,000 BTUs per hour. Homes measuring 2,000-2,500 square feet: A 4-ton unit is necessary.