Tempest Variable Speed Electric PPV Fan: High-CFM Ventilation with NEMA-4 Protection for Fire and Industrial Use

Gasoline PPV fans move serious air, but they come with real trade-offs: exhaust fumes inside a structure, fuel logistics, combustion noise that drowns radio communication, and outright prohibition in any environment with flammable vapors. The Tempest Variable Speed Electric PPV Fan series was designed to close that performance gap. With up to 15,663 CFM from a 110V outlet, a NEMA-4 rated drive that survives wet-environment deployment, and variable speed control that lets an incident commander dial in exact airflow rather than running full-throttle or nothing, this series occupies a category most electric fans have never reached. If your ventilation strategy still defaults to gasoline because you assumed electric couldn’t keep up, the VS series is worth a second look.

What is a Tempest Variable Speed Electric PPV Fan and how does it work?

A Tempest VS series fan is a positive pressure ventilation unit powered by a variable speed electric motor, available in 16″, 21″, and 24″ blade configurations, producing between 11,475 and 15,663 CFM depending on model. It uses an electronic variable speed drive to modulate motor RPM continuously, allowing airflow output to be adjusted at the unit rather than fixed at a single operating point.

The drive is NEMA-4 rated, which means it is constructed to resist windblown dust, splashing water, and hose-directed water from any direction — conditions that are routine in both active fire suppression scenes and industrial washdown environments. The fan draws power from a standard 110V/60Hz source, which eliminates the need for a dedicated high-voltage circuit in most deployment scenarios. Motor options range from 0.5 HP on the 16″ model up to 2.0 HP on the 24″ model, giving fire and industrial crews a documented power-to-airflow ratio for each configuration rather than a generic performance claim.

What does NEMA-4 certification mean for a PPV fan drive, and why does it matter in wet environments?

NEMA-4 is an enclosure rating defined by the National Electrical Manufacturers Association specifying that the enclosure provides protection against ingress of solid foreign objects, windblown dust, rain, splashing water, and hose-directed water. For a variable speed drive mounted on a PPV fan deployed at a structure fire or industrial incident, this matters because unrated electronic drives fail when hit with hose overspray or rain — often at the worst possible moment.

Standard variable speed drives use ventilated enclosures for thermal management, which leaves them exposed to moisture and particulates. The Tempest VS series uses a sealed NEMA-4 enclosure specifically to prevent that failure mode. This makes the VS series viable for deployments where a competitor’s open-drive fan would require protection tenting or simply would not be placed — including outdoor staging in rain, post-suppression overhaul ventilation, and industrial facilities with regular washdown cycles. The NEMA enclosure type standard provides the full protection criteria for each rating class.

How does the Tempest VS series compare across its 16″, 21″, and 24″ models?

The VS series offers five distinct models spanning three blade diameters and four motor sizes, so the right selection depends on matching CFM requirement to power availability and apparatus storage constraints. Each model has a documented weight and output that makes the comparison concrete rather than approximate.

The VS-16-M-0.5 (16″, 0.5 HP) produces 11,475 CFM at 78 lbs., the lightest unit in the series and the easiest to stage in tight industrial corridors. The VS-21-M-0.5 (21″, 0.8 HP) matches that 11,475 CFM figure at 86 lbs., while the VS-21-G-1.5 (21″, 1.5 HP) steps up to 13,414 CFM at 99 lbs. The VS-21-R-2.0 (21″, 2.0 HP) reaches 14,836 CFM at 108 lbs. The VS-24-R-2.0 (24″, 2.0 HP) delivers the series maximum of 15,663 CFM at 119 lbs. All five models operate on 110V/60Hz, meaning any standard commercial or industrial outlet supports deployment without special wiring. The weight range of 78 to 119 lbs. across the series is manageable for a two-person crew with the unit’s solid rubber wheels on uneven terrain.

Why does variable speed control matter for PPV ventilation tactics?

Fixed-speed PPV fans operate at one airflow rate regardless of conditions, which forces incident commanders to manage ventilation openings as the only control variable. Variable speed control adds a second dimension: the fan’s own CFM output can be ramped up or reduced as the incident evolves, without moving the fan or adjusting inlet and exhaust openings.

In fire suppression scenarios, this means a crew can begin ventilation at reduced CFM to establish a controlled pressure cone before increasing output, rather than immediately flooding the structure at maximum airflow. In industrial applications such as confined space entry or post-spill vapor clearance, variable speed allows an operator to match airflow to the calculated air change rate required by the job safety analysis rather than over-ventilating and potentially disturbing contaminated material. The Tempest VS series provides this control continuously across its full operating range, not just at two or three preset steps. That operational flexibility is the core reason the VS series exists as a separate product line from Tempest’s fixed-speed electric fans.

How does the Tempest VS series approach gasoline fan output without combustion?

Most electric PPV fans in the market produce airflow in the 5,000 to 10,000 CFM range, which puts them well below the output of a mid-size gasoline fan. The 15,663 CFM rating of the VS-24-R-2.0 model closes that gap substantially, operating at airflow levels that were previously the exclusive domain of combustion-powered equipment.

The practical implication is elimination of the trade-offs that come with gasoline: no exhaust carbon monoxide being introduced into a structure during ventilation, no fuel storage or transport requirements on apparatus, no combustion engine noise that reaches 90+ dB and interferes with crew communication, and no risk of ignition in flammable-vapor environments where a running gasoline engine represents an ignition source. For industrial facilities with vapor exclusion zones or facilities handling flammable materials, a gasoline fan is not simply inconvenient but in many cases operationally prohibited. The Tempest VS-24-R-2.0 provides 15,663 CFM through a 110V cord in those environments.

What are the storage and deployment characteristics of the VS series?

The VS series uses a foldable handle design that reduces the unit’s footprint for apparatus compartment storage and facility storage racks. Combined with solid rubber wheels, the fan can be transported over rough terrain, threshold lips, gravel staging areas, and uneven industrial floors without requiring a separate dolly or cart.

The 110V/60Hz power requirement is a deliberate design choice for deployability: standard commercial and industrial facilities have 110V outlets at routine intervals, meaning the fan can be staged, plugged in, and operating without locating a generator or a high-voltage outlet. At the heaviest configuration (VS-24-R-2.0 at 119 lbs.), the unit is a two-person lift, but the wheel mobility reduces carry distance to a minimum. The series is designed, fabricated, and built in the USA at Tempest’s facility in Fresno, California, which supports parts availability and service turnaround for domestic fire departments and industrial operators.

Where is the Tempest Variable Speed Electric PPV Fan series used?

The VS series is deployed across fire suppression and overhaul ventilation, industrial smoke and vapor removal, confined space pre-entry ventilation, and post-incident structure clearance. The combination of NEMA-4 drive protection, variable CFM output, and 110V operation covers a wider application range than either a fixed-speed electric fan or a gasoline fan can address individually.

Fire departments using the VS series benefit from the same apparatus storage efficiency as other Tempest electric fans, and the variable speed functionality extends usability to scenarios where full-throttle ventilation would be counterproductive. For a broader selection of electric and gas-powered ventilation options, the Blowers and Fans Catalog and the Firefighting Catalog | PE-Energy Industrial Supply cover the full Tempest line alongside complementary brands. Industrial buyers comparing the VS series to battery-operated alternatives should also review the Tempest VS-1.3M Tech Series Powered by MILWAUKEE for cord-free deployments where a 110V outlet is not available. Buyers who need a single high-output electric fan without variable speed can evaluate the Tempest 24-IND Electric Powered Fan as a fixed-speed alternative at the 24″ blade diameter. For facilities requiring a broader ventilation equipment supply, Euramco Safety Products offer complementary gas and air-driven fan options for industrial and hazardous-area applications.

When is the Tempest VS series the right choice, and when is it not?

The Tempest VS series is the correct selection when the application requires variable airflow control between 11,475 and 15,663 CFM, operates in wet or dusty environments where a NEMA-4 drive is necessary, prohibits combustion engines due to flammable vapor risk or exhaust contamination concerns, and has reliable access to a 110V/60Hz power source.

It is not the right choice for remote deployments with no electrical infrastructure and no generator, where a gasoline-powered PPV fan remains the practical option. It is also not the first choice when apparatus storage space is critically limited and a battery-powered cordless unit like the VS-1.3M Tech Series would reduce deployment complexity. At 78 to 119 lbs., the VS series is not a one-person carry for all models, which matters for single-responder or light rescue applications. Within those constraints, the VS series delivers a documented combination of NEMA-4 wet-environment protection, 15,663 CFM maximum output, and variable speed control that no fixed-speed electric fan in the same size class provides.

Tempest Fire & Industrial

Variable Speed Electric PPV Fans

16″–24″ Sizes | NEMA-4 Drive | Up to 15,663 CFM | Made in USA

Overview

The Tempest Variable Speed (VS) electric fan series bridges the gap between gasoline and electric airflow — delivering up to 15,663 CFM with the precise adjustability of electric variable speed drive technology. A NEMA-4 rated drive provides extra protection in wet environments, making the VS series suitable for industrial environments where moisture is a concern.

Available in 16″, 21″, and 24″ blade configurations with multiple motor options, the VS series covers a wide range of flow requirements. The foldable handle and 110V operation make these fans highly deployable in fire and industrial settings.

Models & Ordering Information

Manufacturer: Tempest — 4708 N. Blythe Avenue, Fresno, California 93722 USA — tempest.us.com