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HVLS fan service

High volume, low-speed (H.V.LS) fans move large volumes of air and generate a steady, light breeze, creating an evaporative-cooling effect that reduces a facility’s effective temperature by as many as 12 deg. F.  These units are also energy savers in that the floor to ceiling air movement they create helps improve air conditioning system efficiency. In fact, an HVLS fan can make it possible to increase the air-conditioning thermostat setting by 5 deg. F with no change in employee comfort.While the warm weather benefits of H.V.L.S fans are commonly understood, smart facility managers realize that operating them during the summer is just the tip of the energy savings iceberg. Here are four tips for maximizing ROI on a year round basis.

Right fan in the right place

Several factors must be considered when deciding how and when to use HVLS fans. They include obstructions such as pallet racks, machinery and product staging, personnel work areas, and overall building layout. Larger-diameter fans (24 ft. dia.) will move air further down rack aisles and over obstructions. Small-diameter fans (8-, 10- and 12-ft.) are most effective in specific work areas. In recent years, floor-mounted HVLS fans also have become available where overhead obstructions preclude the use of traditional ceiling mounted HVLS fans.

centralized controls

Advanced HVLS fans can cover an area as large as 22,000 sq. ft., in some facilities that isn’t enough. In those instances, a fan array driven by a centralized control system is required.

Segment space with fabric curtain walls

Small spaces take less energy to heat or cool than large spaces. Unfortunately, industrial facilities tend to encompass large, wide-open areas. Therefore, flexible fabric curtain walls can be an important supplement to HVLS fans. As an economical way to partition space, these curtain walls can maximize the effectiveness of a facility’s entire HVAC/HVLS environment-control system by segmenting off areas that require extensively treated air, further minimizing waste

Before purchasing HVLS fan how do you evaluate ?

  • Motor Output Torque at max Speed
  • Motor Output Power at max Speed
  • Motor Input Power at max Speed
  • Sound Level [dB]
  • Air Flow [CFM]
  • Weight [Lb]
  • Warranty
  • Maintenance Schedule

Let us examine one by one,

Motor Output Torque :

Assuming you have the correct blade profile, this parameter is essential to move the blades at the required speed. If the blades don’t move, air particles cannot be displaced, and air can not flow. For example, Epoch 1.0 produces 50Nm of torque at a speed of 200 rpm. Epoch 2.0 delivers 90Nm at a rate of 100 rpm and 140Nm at a speed of 55 rpm. Epoch 3.0 produces 170Nm at a speed of 60 rpm. For the blade profile we have, these values represent a peak output power of about 1100W. That means that energy will move the air particles. Now, if we were to use a lower speed, these values drop off precipitously. Also, If we were to use lighter blades, the power will be reduced as well. Lighter blades do not necessarily mean the same airflow. More massive blades do not necessarily mean more air flow. Epoch HVLS fans produce the most airflow per Watts of motor power. Assuming that the HVLS industry has standardized on reasonable efficient blade profiles, our conclusion is:Air Flow is proportional to Motor Output Power. Bigger blades require more torque than smaller blades. See our chart below for various blades.

 Motor Output at Max Speed :

 This is related to the argument made above. Lighter blades do not necessarily mean the same airflow. Heavier blades do not necessarily mean more air flow. Assuming that the HVLS industry has standardized on reasonable efficient blade profiles, our conclusion is: Air Flow is proportional to Motor Output Power.

 Motor Input Power at Max Speed :

 Most companies do not give you data for the output power. The evidence for input power is readily available. The Power is an indication of the efficiency of the motor and drive system. Usually, a geared motor would be 60% efficient compared to a direct drive motor which could be 85% efficient. Higher input power does not necessarily mean that it is converting into the air flow.Air Flow is NOT proportional to Motor Input Power.

Sound Level [db]:

Most companies do not perform this test. However, we can comfortably identify silent fans from the noisier geared fans. Gears may not fail, but they would start getting louder and more boisterous over a period. The sound is an essential aspect of fan performance. Not all direct drive fans are quiet. Sound signature depends not only on the motor construction but also on the motor inverter and software inside it. Epoch fans are the softest in the industry.

 Air Flow [CFM]:

 Most companies do not publish this number. They prefer to use air velocity numbers (m/s) which are meaningless for most of the end consumers. Standardized testing of this parameter would be most beneficial to the end users.

Weight [Lb]:

 HVLS fans with geared motors can weigh as much as 350 lbs. Almost twice as much as direct drive fans. So considering a geared fan is a fool’s game. It is a safety issue, and it is an unnecessary amount of metal hanging from the ceiling. Then again not all direct drive HVLS fans are created equal. Some are deficient power, others overheat. 


 It is excellent to see some great warranties in HVLS industry. More extended guarantee gives you the best comfort of mind. Direct drive fans could last you a lifetime but not so is the case with geared fans.

Maintenance Schedule:

This is a fun one. If it is not a direct drive fan, there is maintenance required of all gearboxes at some point in time. First, they start making noises, and after that, they would begin to move erratically. Oil would need to be changed in these gearboxes as well at some point in time. Whereas, direct drive fans should require no maintenance over their lifetime.

our factory trained installers, installation is a breeze. With low operating costs of around a dollar a day. In the event that  HVLS fans fail, it’s important to reactivate uptime as quickly as possible. Often, this is the key component to a building’s climate and humidity control. The best way to get your HVLS fan repaired and back to  stir air is to reach out to an H.V.L.S expert who can identify and remedy the issue promptly.


Call us now for sales, Service and install H.V.L.S Fan Phone: [ 832] 232 -9150, 24/7 Emergency service .