CFM is Key - Don’t Be Fooled By Wind Speed
Are you buying a new ceiling fan? Perhaps you’re wondering why the one you have doesn’t cool down your room? The efficiency of your ceiling fan is determined by the amount of air it can circulate, each time. What is CFM?
- CFM stands for Cubic Feet per Minute
- It is the rate at which your ceiling fan can move air
There are many different ceiling fans on the market, but you need to select a model that is going to work in your space. To do that you need to select the correct CFM rate, not wind speed.
Do not fall prey to marketing about wind speed. This measure does not show you if the ceiling fan you have or are thinking of buying, will work well in your space. Two fans can have the same speed but vastly different CFM ratings.
Compare this to a car. Yes, any car can reach a speed of say 50 MPH but if you are climbing up a steep road a less powerful model will not handle the conditions as easily. The potential cooling power of your fan is determined by its CFM. You can step on the gas in a less powerful model but you’re never going to zip up that steep road as easily as you can with a more powerful engine.
Size Counts - What is the CFM of your ceiling fan?
In the same way, the power of your ceiling fan is determined by the strength of its motor and capacity to circulate air. Do you need to cool down a large room, or an average-sized room?
- Are you lying under your fan to get cool?
- Is your ceiling fan the right size?
- Good CFM ranges from 4,000 to 5,000
- Better ranges from 5,000 to 6,000
- Best is over 6,000
Wind Speed, Power & Fans
The speed of your fan is not what is going to cool you down, at night. The fastest-moving air is directly under the blades. As air is forced down it is going to find resistance – your furniture, your floor, and walls. It will recirculate and move in a continuous pattern. Air will be displaced and move – cue, cooling breeze. With the right model and placement, your ceiling fan can bring down the temperature of your room.
Small Space Cooling vs Larger Rooms
Do you have the same model fan in your guest room as you do in your bigger, main bedroom?
Your guests might rave about what a great night’s sleep they had while you tossed and turned. In the smaller room. Your guest room ceiling fan was able to efficiently recirculate air and cool down the room. The bigger volume of air in your room meant that your room was warmer, and you ended up plugging in your free-standing box fan – for some relief.
This has nothing to do with the speed of your fan – but the size of the CFM.
Environmental Protection Agency Requirement
All ceiling fan manufacturers are required by law to display the exact power capacity and CRM of each model. Check out graphics on the boxes, brochures, catalogs, and online. This will show you:
- The airflow
- Energy efficiency
- CRM number
Ceiling Fan Blades, Sizes, and Styles
There are few good rules of thumb to remember when looking at blades. Blades do affect the circulation of air but the effect is minimal compared to the CRM. The power of the circulation of air is not determined by the blades, blade-span, or material.
- Longer blades work best in larger rooms
- Provide soft, comfortable air-flow
- Shorter blades are great for smaller rooms
- Fans with more blades are quieter, less ambient noise
Timber fans are a popular choice for bedrooms as they are quieter. The more blades there are, the more drag there can be on the motor. Industrial fans usually only have two or three blades, for this reason. ( E.g. Turbines)
Ceiling fan blades are a great design feature and can be chosen to enhance the style of your room. Have you seen timber palm-shaped blades? Some five-star hotels use them to create that old-world, luxury feel.
Outdoor Living Patio Ceiling Fans
Do you enjoy relaxing with your family on your outdoor patio? Do you have a covered deck or patio? Installing a ceiling fan can provide a much welcome breeze to cool off your guests. Imagine dropping the temperature down from 98 degrees to 91. It might still be warm but circulating the air will make the heat of summer more bearable.
Go Green and Save Money with New DC Ceiling Fans
You can save a lot of money using ceiling fans to cool your home. In general, the cost of running ceiling fans is much less than air-conditioning. In California, in Summer, 50% of a home's energy cost is from AC. The energy needed to power AC is huge – across the United States, 17% of all energy used in homes is from air conditioners.
There are two types of ceiling fans that you can choose from. There are AC and DC options, for powering ceiling fans. Newer, DC fans use two-thirds ( 67%) less energy than AC fans. AC fans run straight from the power outlet while DC fans convert alternating current ( AC) to direct current. ( DC)
The initial cost for DC models is higher, but the long-term savings are huge. A DC fan uses 30 Watts which translates into about 1 cent per hour!
CFM EPA Regulations
All ceiling fans manufactured and sold in the United States are sent to testing facilities. This is done to check and test their CFM rating, and not the wind speed. The measurement of airflow and the amount of air that is can be circulated is determined by the CFM.
In the same way that a powerful car can accelerate quickly and roar to life, so to can a ceiling fan with a larger CFM. The power of your ceiling fan is from the power of the motor, and not the speed of the air.
Don’t be fooled. Check out the CFM or get expert advice to choose a model that is going to work best, in your space.