BTU: What It Is, and Why It Is Important

If you’ve been shopping around for air conditioning units, you may have already come across the acronym BTU in product guides and specifications. Let us give you an overview of how BTUs can help you buy the right AC for your home.

What Is a BTU?

BTU stands for British Thermal Unit and measures the amount of heat needed to raise one pound of water by one degree at sea level. In terms of air conditioners, the specifications indicate how many BTUs it can remove from the air, per hour. The higher the number of BTUs, the faster it can cool a room. For reversible HVAC systems, there may be separate BTUs for heating and cooling.

Higher Doesn’t Always Mean Better

It should be noted that when it comes to BTUs, it has to be in proportion to the size of the room. Higher doesn’t always mean better. Air conditioners work by pumping out cool air, cycling off when it reaches the desired room temperature, and cycling back on when the temperature goes above the threshold. AC units with high BTUs, when installed in a proportionally small room, will tend to pump out cool air in bursts instead of gently cycling on and off. Conversely, using a unit with low BTUs in a large room won’t be as effective, and the AC unit will be on maximum all the time. In either case, the air conditioner gets overworked, resulting in a shorter lifespan and a much higher energy consumption.

Calculating BTUs

Many websites and product guidelines include recommended BTUs based on room size, but there are several factors that could affect your room’s actual requirements. Factors such as elevation and amount of direct sunlight that streams into a room are considered; infrared light from the sun is a source of heat, after all. There’s also the insulation and energy-efficient windows to be considered.

Ultimately, if you’re unsure of your room’s BTU requirements, hiring an HVAC professional to inspect your room is your best option. They take all factors into account, including others like the number of occupants, and the room’s moisture levels, which is an important factor for areas such as the kitchen.

To learn more about getting the right air conditioning units for your home, call Cardinal Heating & Air at (425) 827-9997 or fill out our contact form to schedule a consultation. We are located in Kirkland, WA and serve nearby areas.