Quick Guide — Hamilton Air HERO-5 V300i
|
Coverage per fan (optimal) |
7,3 m |
| Coverage per fan (optimal) | 2.000–2.500 m² |
| Optimal ceiling height | 6–12 m |
| Rated airflow rate (CFM) | 316.000 CFM |
| Wind speed at floor level | 0,5–1,0 m/s |
| Recommended fan spacing | 38–42 mc/c |
| Operating fuel consumption | 3.0 kW max |
CFM
Airflow, measured in cubic feet per minute, is the volume of air that a fan moves per minute.
"The specifications state 300,000 CFM. So, how cool does that mean my warehouse will be?"
What does this mean for you?
CFM indicates the total air circulation capacity of a fan. A higher CFM means the fan can push more air per minute—this results in a stronger airflow at the floor, more efficient evaporative cooling, and faster flattening of ceilings. But CFM alone doesn't tell you how cool a specific person standing in a specific position will feel. To know that, you need to consider the wind speed at the floor —the velocity of the air actually reaching people in that space.
Here's the practical relationship: a Hamilton Air HERO-5 V300i blower with a diameter of 7.3m will generate an airflow of approximately 316,000 CFM at maximum speed . When this airflow reaches the floor area of 2,000m², it creates an average wind speed of 0.5–1.0 m/s—the range that human physiology requires for effective evaporative cooling. Below 0.3 m/s, cooling efficiency decreases sharply. Above 1.2 m/s in a low-activity office environment, it feels like a draft (although in a dynamic warehouse environment, higher speeds are often preferred).
The reason CFM stands out in technical specifications is because it's an objective, measurable number that allows for comparisons between brands . But it's only a starting point, not an end point. Two fans with the same CFM rating but different blade shapes or installation heights will produce different comfort levels at floor level. Always request airflow data certified by AMCA —this means the CFM figure has been tested under standard conditions, not calculated theoretically.
CFM Ratings — Hamilton Air HERO-5 (at Max Speed)
V300i — Ø 7.3m | 316,000 CFM
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V300i — Ø 6.1m | 240,000 CFM
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V300i — Ø 5.5m | 196,000 CFM
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V200i — Ø 5.0m | 154,000 CFM
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V200i — Ø 3.6m | 90,000 CFM
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Diameter
The blade span — the single biggest driver of how much floor area one fan covers
"7.3m is listed as the coverage diameter — but does that mean 7.3 meters of floor is all I get from one fan?"
Floor Coverage by Diameter — Hamilton Air HERO-5
What This Means for You
No — the 7.3m diameter refers to the blade span of the fan itself, not the floor coverage area. The floor coverage of a 7.3m fan is dramatically larger than the fan blade circle: 2,000–2,500m² — roughly 50 meters in diameter at floor level. This is because the fan pushes a high-volume column of air downward, which then spreads horizontally across the floor like water spreading from a tap. The larger the fan diameter, the wider and more powerful this spreading airflow becomes.
Think of it this way: a 7.3m fan sitting 9m above the floor is pushing a column of air down through 9 meters of vertical space. During that descent, the air column expands. By the time it reaches floor level, the effective coverage zone has a diameter of approximately 50m. The floor coverage area (roughly 2,000m²) is about 22× larger than the fan blade area.
This is why choosing the right diameter matters so much for project economics. Undersized fans require more units to cover the same area — a building specification calling for 3.6m fans where 7.3m fans are appropriate might require 5–6 units instead of 2–3 units, nearly doubling installation cost and complexity. The relationship between diameter and coverage is roughly quadratic: doubling the diameter roughly quadruples the coverage area, making larger fans dramatically more cost-efficient per square meter covered.
However, larger is not always better. A 7.3m fan requires ceiling clearance and structural mounting capacity that smaller buildings cannot provide. The minimum practical ceiling height for a 7.3m fan is approximately 5.5m — and the optimal height range where coverage is maximized is 6–12m. Below that, the larger fan is not fully effective. Above 14m, even the 7.3m fan may need a drop rod to bring it closer to the optimal operating zone.
03 — The Variable Most People Underestimate
Ceiling Height: The Multiplier That Changes Everything
Two identical 7.3m fans in different ceiling heights produce dramatically different floor coverage — and different levels of comfort. This is the variable most facility managers underestimate when planning their HVLS installation.
Height | What happens to airflow | Coverage (Ø 7.3m) |
Under 4m | Fan too close to floor — air column doesn't have distance to spread. Coverage zone is narrow; airspeed at floor is high but localized under the fan only. | 600–900 m² |
4–6m | Air column has some spreading distance. Coverage is adequate but below optimal. Smaller fan diameters (3.6–5.5m) are better matched to this height range. | 1,000–1,400 m² |
6–10m ★ | Optimal range for 7.3m fans. The air column reaches full spread diameter before hitting the floor. Maximum coverage area, best airspeed uniformity, ideal destratification effect. | 2,000–2,500 m² ★ |
10–14m | Air column continues spreading but floor-level airspeed begins to decrease as the volume disperses over a larger area. Coverage diameter is larger but airspeed threshold (0.3 m/s) requires some adjustment. | 1,600–2,200 m² |
14m+ | Very high bays require either a drop rod to lower the fan to the 8–10m effective operating zone, or a higher-CFM model. Without adjustment, floor-level airspeed drops below effective cooling threshold at full coverage area. | Reduced — needs adjustment |
Fan Spacing: Why 15–20% Overlap Isn't Optional
Spacing fans correctly is where most under-specified HVLS installations fail. Two fans that individually cover 2,000m² each do not automatically give you 4,000m² of comfortable coverage when installed together — unless they're positioned correctly.
The Core Principle
The "coverage area" of an HVLS fan is not a sharp boundary — it's a gradient. Airspeed is highest directly below the fan and decreases toward the edges of the coverage zone. If you position fans so their coverage zones just touch with zero overlap, you create a low-airspeed dead zone at every midpoint between fans — exactly where workers spend significant time during shift changes and equipment transitions. The 15–20% overlap standard ensures no point on the floor drops below the 0.3 m/s effective cooling threshold.
For a pair of HERO-5 V300i fans (7.3m, covering 2,000m² each with an effective diameter of ~50m at floor level), the recommended center-to-center spacing is 38–42 meters. At this spacing, the coverage zones overlap by approximately 15–20% in the middle zone between the two fans — ensuring the midpoint airspeed stays above 0.5 m/s.
Spacing guidelines change slightly based on ceiling height: lower ceilings (where fan coverage is narrower) require tighter spacing; higher ceilings in the optimal range allow slightly wider spacing as the coverage diameter is larger. The BigFans.vn free layout design service calculates exact spacing for your ceiling height and floor plan automatically.
✦ Recommended
15–20%
Coverage overlap
Ensures no dead zones. Midpoint airspeed stays above 0.5 m/s. Spacing: 38–42m c/c for 7.3m fans at 8m ceiling.
✓ Adequate
10–15%
Coverage overlap
Midpoint airspeed acceptable (~0.35 m/s). Workers will notice the gradient. Acceptable for low-occupancy zones or aisles.
✗ Avoid
<10%
Coverage overlap
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05 — Learn From Others
4 Sizing Mistakes That Make HVLS Fans Feel Like They "Didn't Work"
Almost every case of "we installed HVLS and it didn't solve the problem" traces back to one of four planning errors — none of which are the fault of the technology.
1.Choosing fan diameter based on price, not ceiling height — and getting the wrong size for the space
Common · High Impact
Fix: Match fan diameter to ceiling height first, then adjust quantity to cover floor area. For 8–12m ceilings, specify 7.3m fans. For 4–6m ceilings, specify 3.6–5.0m fans. Never compromise on diameter to reduce unit cost — the cost-per-m² of coverage still favors larger fans even at higher unit prices.
2. Spacing fans for zero overlap — creating dead zones exactly where workers gather between tasks
Very Common · High Impact
Fix: Always specify 15–20% coverage overlap. For HERO-5 V300i (7.3m) at 8m ceiling, this means maximum 42m center-to-center spacing. If budget limits the number of fans, it is better to cover less total floor area with correct overlap than to cover more floor with inadequate overlap.
3. Not accounting for structural obstructions — mezzanines, large racks, and HVAC ducts block airflow
Moderate · Medium Impact
Fix: Share your floor plan and rack layout with BigFans.vn engineers as part of the free layout design. Obstructions are identified and additional fans are specified for sheltered zones. This is particularly important for high-bay racking DCs where multiple tall rack bays can create significant shadow zones.
4. Running fans at low speed constantly — defeating the cooling physics to reduce noise
Common · Medium Impact
Fix: Hamilton Air HERO-series motors operate at 45–55 dB(A) at full speed — already quieter than most industrial AC systems. If noise is a concern, the issue is typically not the fan but reflective surfaces in the facility amplifying sound. BAS-integrated adaptive speed control automatically adjusts fan speed based on temperature — running at high speed when needed, lower speed during cooler periods — optimizing both comfort and noise profile automatically.
The Questions People Ask Most About HVLS Coverage
Coverage depends on fan diameter and ceiling height. A Hamilton Air HERO-5 V300i at 7.3m diameter covers 2,000–2,500m² at optimal ceiling heights of 6–12m. A 5.5m model covers 1,100–1,400m². A 3.6m model covers 500–700m². Coverage decreases for very low ceilings (under 5m) or very high ceilings (over 14m without a drop rod). All coverage figures are AMCA-certified at minimum 0.3 m/s airspeed boundary at floor level.
CFM (Cubic Feet per Minute) measures the volume of air a fan moves per minute. Higher CFM means more air movement and stronger floor-level airspeed. For sizing purposes, look for AMCA-certified floor-level airspeed data (0.5–1.0 m/s is the effective cooling range) rather than just CFM alone, since two fans with identical CFM but different diameters or mounting heights produce very different floor-level comfort. A useful rule of thumb: look for at least 150 CFM per square meter of intended coverage area.
The industry standard is 15–20% coverage overlap between adjacent fans. For a HERO-5 V300i (7.3m) at 8m ceiling with ~50m effective floor diameter, this means 38–42m center-to-center spacing. Spacing fans too far apart (under 10% overlap) creates low-airspeed dead zones at the midpoints between fans — the most common cause of "HVLS didn't work" complaints. For very high ceilings (12m+), reduce spacing slightly to compensate for decreased floor-level airspeed.
Yes — significantly. The optimal operating height for a 7.3m fan is 6–12m. Below 5m, the air column doesn't spread far enough before hitting the floor, reducing coverage diameter. Above 12m, floor-level airspeed decreases as the column disperses over a larger vertical distance. For very high ceilings (14m+), a drop rod to lower the fan to the 8–10m effective operating zone restores full coverage performance. BigFans.vn engineers specify the correct drop rod length for each project during the free layout design process.
Basic formula: (Floor Area ÷ Coverage per Fan) × 1.15 for 15% overlap, rounded up to the nearest whole number. For a 5,000m² factory at 8m ceiling with 7.3m fans (2,250m² coverage each): 5,000 ÷ 2,250 = 2.2 × 1.15 = 2.5, rounded up to 3 fans. Adjustments needed for: high ceilings above 12m (reduce coverage per fan by 10–20%); major structural obstructions; high-heat zones near machinery. The calculator on this page handles all these adjustments automatically. BigFans.vn also provides a free professional layout design that accounts for your specific floor plan and obstructions.
Figuring out your airflow needs can be a pain in the ass—especially on your own. Get in touch and let our airflow experts guide the way.
Contact Office & Showroom
📍 Address: 304-306 Truong Van Bang Street, Cat Lai, Ho Chi Minh City
📧 Email: bigfans@hamiltonair.vn
📞 Hotline (24/7 Support): +84 909 899 367
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