Frequently Asked Questions
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A high-volume low-speed (HVLS) fan is a type of mechanical fan greater than 7 feet (2.1 m) in diameter. HVLS fans are generally ceiling fans although some are pole mounted. HVLS fans move slowly and distribute large amounts of air at low rotational speed– hence the name "high volume, low speed."
Typical applications for HVLS fans fall into two classifications—industrial and commercial. In industrial applications, air conditioning is often cost prohibitive or impractical. Fans installed in spaces like warehouses, barns, hangars and distribution centers can prevent heat stress, increase worker comfort and the productivity of both workers and livestock. HVLS fans are also used in commercial spaces, where air conditioning is more common, but increased air movement from ceiling fans can cost-effectively augment occupant comfort or prevent stratification. Typical commercial applications include shopping malls, churches, office buildings, fitness centers and schools.
- Safety assurance: RTFANS’s unique double-layer chassis design make a dual protection to hold the heaviest motor part in main structure, while other suppliers only have single layer.
- Considerate design: RTFANS adopts mortise and tenon structure with welding for the main frame while other suppliers in the market use only welding to connect.
- Bigger airflow: With leading R&D team for HVLS fans, RTFANS brings 20-30% higher air volume than other brands.
More fan blade does not mean more air. It is a balance of total efficiency with consideration of noise level and air volume.
Our first HVLS fan was made with 10 blades and then 8 blades as second generation, now it comes to the 7th generation with 6 blades. We are always trying to improve our fan design with better efficiency. Creating a larger airfoil wasn’t simply the answer to improving efficiency, though. The airfoil must work efficiently through a range of speeds. When an HVLS fan rotates, the end of the blade moves faster than it does at its fixed point at the chassis, the fan blade angle also gives impact to air flow-- While airflow patterns needed strong research and consideration.
When engineers experimented with airfoil shape, they discovered that a larger shape allowed them to reduce the number of blades. Final fan design decreased from 10 to 8 and then 6, without a corresponding drop in fan performance.
Research proved beneficial as reducing the number of blades produced another benefit: reduced torque (the tendency of a force to rotate an object about an axis, fulcrum, or pivot). Fan lifespan is related to torque:
Horsepower = Torque * Revolutions Per Minute (RPM) 5252
As RPM goes up, torque goes down for the same horsepower. Our engineers also found that, due to the longer airfoil shape, 6-blade HVLS fans rotated faster than 8 or 10-blade fans, which lowered torque. Since torque is a constant stress on a fan’s motor, bearings, and gear, less torque meant longer fan life.
- RTFANS is the leading solution provider in China focus in air ventilation and cooling products and system since 2003. It has rich experiences in both product and system- means it can not only provide you with high quality product and competitive prices but also can help you to solve your problems and meet your different requirements on ventilation and cooling, especially on large space area.
- RTFANS is the leading brand in China in HVLS fans and has good reputation in the market. The first HVLS industrial ceiling fan was made by RTFANS team in 2008. We have a strong technical support team and we are leading in HVLS fan R&D in China.
- RTFANS provide you not only product but also service including installation training and after-sales service guidance.
- RTFANS give lifetime warranty for its mechanical parts and 3 years warranty for its electrical parts to the industrial HVLS fan products.
Larger diameter fans(HVLS) can move more air than traditional smaller fans at the same speed. A turbulent, high velocity air jet dissipates very quickly. A large column of air, however, “travels” farther than a small one due to the friction between moving air and stationary air, which occurs at the periphery of the moving column. The perimeter of an air column varies directly with column diameter. While the cross-sectional area varies with the square of the diameter, the large column has proportionately fewer peripheries, and therefore less “drag.” The air column from a 3 feet (0.91 m) diameter fan, therefore, has more than six times as much “friction interface” per volume of air moved as does the air column from a 20 feet (6.1 m) diameter fan.
When the down column of air from an HVLS fan reaches the floor, the air turns in the horizontal direction away from the column in all directions. The air flowing outward is called the “horizontal floor jet.” Since the height of the floor jet is determined by the diameter of the column of air, a larger diameter fan naturally produces a larger air column and thus a higher floor jet.
Smaller high-speed fans of equivalent displacement are incapable of producing the same effect.
The power to drive a fan increases roughly with the cube of the average air speed through the fan. A commercial fan delivering air at 20 miles per hour (mph) requires about 64 times as much power as a similar sized fan delivering air at five mph.
Airspeed, combined with fan “effectiveness,” means that when the objective is to cool people or animals, very large, low-speed industrial and commercial ceiling fans are more efficient and effective than small high-speed fans.
Yes，It is very expensive .Most HVLS fan is made in USA and China .A few manufacturer in India produce HVLS fan. But almost all manufacturer do not have after-sales service. If HVLS fan goes wrong ,you have to think about the cost of maintenance .The fee of accessories ,freight and labor costs is too high . Although it is just a glitch ,you may be lost a lot of money. When you choose the HVLS fan ,you should think about the quality of fan and after-sales service.
The HVLS fan of 3 fan blade is cheaper than other HVLS fan .HVLS Ceiling fan of 3 fan blade existed in the market. .Certainly , a few manufacturer is providing this kind of HVLS fan.However,3 fan blade is gradually replaced by 5 or 6 fan blade .Actually , the airflow depend on the fan blade and rotating speed . Generally speaking, the more No. of fan blade ,the bigger airflow .HVLS fan of 3 fan blades has smaller airflow and application . Although the HVLS fan of 3 fan blades is cheap ,it is not useful for big space. If you want to find solution for big space ventilation and cooling ,maybe HVLS fan of 6 fan blades is your better choice.
Yes, HVLS fan can help you to cool a large apace. HVLS fan is high volume low speed fan .It can provide perfect solution for big space ventilation and cooling. HVLS fan can be widely used in workshop, warehouse, school, church, bus station, mall and almost all places with big space and high roof. One RTFANS HVLS fan can cover more than 1000sqm just with 1.5KW. The RTF-DF-7E fan can cover 1600sqm.If you have a factory or warehouse of 10000sqm,RTFANS also can provide solution for you.
If having had an excellent HVAC system , that you have one or more HVLS fan is a good choice. HVAC system has high power. It cost a huge when AC system fully running, while the HVLS fan can spread the cold air into every corner of the space during AC running, make it more well proportioned . During Spring or Autumn when temperature keep in a range from 20-30 ℃, for those space with AC system, it ' s awkward to decide if need to run the AC system, while with HVLS fan, you can forget the electricity bill caused by HVAC system. 7%-10% saving in electric power consumption by setting AC temperature 1℃ higher.14%-20% saving in electric power consumption by setting AC temperature 2℃ higher.
It is cheap and Cost-effective. Compared with traditional solution for big space ventilation and cooling ,HVLS fan has big advantage ,Here is the form for your inference:
|HVLS Fan||Powerful Fan|
|Fan Diameter (m)||7.3||0.75|
|Air Flow (m³/min)||13,500(810,000)||300(18,000)|
|Effective Area (m²)||1,500||30|
|Total Units installed||6||300|
|Total Kw Installed||9||108|
@10hrs/day @26 days/mth
From this form ,we can know that the No. of powerful fan is more than HVLS fan and need more power than HVLS in big space ventilation and cooling .Actually ,powerful fan is more expensive than HVLS fan in this situation.
Please contact RTFANS for complete ventilation & cooling solution.
Yes, an HVLS fan relies on size, not speed, just with a power of 1.5kw to move a large scale of nature wind which lead to the double function of ventilation and cooling. One fan can cool up to 1000m2.
With nearly 20 years industry experience in the filed of ventilation and cooling. As the leading brand in HVLS fan in China, RTFANS is working with the first HVLS fan team now and leading the direction in R&D. RTFANS Series HVLS fan is the lasting seventh generation with more higher-level safety assurance such as Double Chassis, Mortise and tenon Joint, Patented design fan blade with Full connection and Separated connection reinforce support.
Yes, the kind of winglets is always seen among airplanes and motorcycle races, but it is not designed for beauty. Eddies will be formed in the end of the fan blade while HVLS fan is running. With winglets, the part of energy loss will be avoided, and it makes fan work more stable.
Each fan includes:
- “Nord” motor
- 6 fan blades
- “DANFOSS” frequency converter
- Installation accessories
The smallest size of HVLS ceiling fan is 2.8 meters(diameter), and the largest is 7.3 meters(diameter). So, the available fan size is from 2.8m to 7.3m, you can customize your fan blade size as your wish.
Yes. Of course. The fan speed can be adjusted by rotating the speed control knob on the frequency converter.
It’s generally about 12 to 15 years. The specific use varies from person to person. Different use place, use frequency, use method and so on can cause the influence of varying degrees to the fan’s life span.
The appropriate operating environment temperature for HVLS fan is -10~55℃. Besides, the fan had better not be installed above the equipment with serious heating.
Whether you are worried about the high temperature of workshop, factory, warehouse, whether you are still worried about how to spend the hot summer, especially in southeast Asia, the four seasons only hot, very hot, very very hot and the hottest! Then you need an HVLS fan to cool your factory, a high volume, low speed HVLS fan to cooling and ventilation large Spaces, One HVLS fan can cover 1000m2 with only 1.5KW in power consumption. It’s an energy saving product. You must need it!
You can press the link to watch how to install the industrial ceiling fan. It is easy to install HVLS ceiling fan by yourselves.
- Step 1: Clip on any steel H-beam, without changing any steel structure.
- Step 2: RTFANS Cardan joint allows the fan to make free oscillation and to find its level position no matter what the slope.
- Step 3: Connect the ends of the extension rod with the Cardan joint and drive device by bolts.
- Step 4: The drive device has been assembled to be one unit before delivery, fix it to the extension rod by using bolts.
- Step 5: Please ensure the angle between each steel wire and the drive device is 45°,make sure the drive device of fan at a vertical level position.
- Step 6: Take the bottom cover close to the blade wheel and tighten it by bolts.
Traditional HVLS fans can’t be mounted outdoors, but the portable series can do, moveable fan, can be indoor or outdoor flexible moveable used, it is suitable for outdoor or no fixed position of the work area, like gardens, gyms, playgrounds and so on. It features in excellent quality, resistant to a variety of harsher environment. One portable series fan can cover 600m2 with only 2.95A in power consumption and the longitudinal air supply can reach 30 meters.
With the characteristics of High-Volume and Low Speed , HVLS Fan don’t need sprinkler system.
Different series of HVLS fans require different mounting heights.
Industrial series HVLS fan: clearance from roof to fan blade is 1.2-3m with extension rob, the fan diameter is 3.7m(12’) to 7.3m(24’) and the clearance from floor to fan blade 5-9m.
PMSM series HVLS Fan: clearance from roof to fan blade is 0.5-2.5m with extension rob, the fan diameter is 3.7m(12’) to7.3m(24’) and the clearance from floor to fan blade 5-9m.
Commercial series HVLS Fan: clearance from roof to fan blade is 0.4-2.4m with extension rob, the fan diameter is 2.8m to 4.0m and the clearance from floor to fan blade 3-5m.
All the above conditions are the best installation height.
As long as the building height is above 4.5 meters, it can be installed in steel structure, concrete structure, spherical grid structure or complex structure. There are no special requirements for the installation site, and the plant can be installed with or without driving.
RTFANS HVLS Fan can be widely used in any big space where height above 4 meters. Contact our sales representative to get the installation proposal.
Pls contact our sales representative to get the proposal.
RTFANS can work with almost all HVAC facilities like evaporative air cooler, air conditioning, heating machine, air humidifier etc.
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