Roots Blower vs. Gardner Denver: Which Blower Is Right for Your Industrial Process?

Choosing between a Roots blower and a Gardner Denver blower isn’t just a brand decision it’s a technical and operational one that affects energy costs, maintenance requirements, and process reliability for years. This guide cuts through the marketing and gives industrial buyers the information they need to make the right call.

If you’re a plant engineer, operations manager, or procurement specialist evaluating positive displacement blowers, read this before you specify.

What Is a Roots Blower?

A Roots blower (also called a Roots-type positive displacement blower or rotary lobe blower) is a positive displacement machine that moves air or gas using two counter-rotating figure-eight shaped lobes. As the lobes rotate, they trap a fixed volume of air at the inlet and carry it around the outside of the casing to the discharge without any internal compression.

Key characteristics:

• Fixed displacement per revolution – flow rate is directly proportional to shaft speed
• Pressure rise occurs externally – at the discharge, the trapped air meets system backpressure and is compressed
• Oil-free air delivery – no lubricant contacts the air stream (lobes don’t touch each other or the casing)
• Pressure differential limited – typically 0-15 PSIG for standard Roots-type blowers; higher for tri-lobe designs

The term “Roots blower” technically refers to the original design patented by Philander and Francis Roots in 1860 but has become a generic industry term for all rotary positive displacement lobe blowers.

What Is a Gardner Denver Blower?

Gardner Denver is a manufacturer of positive displacement blowers, not a distinct blower type. Gardner Denver produces Roots-type (twin-lobe and tri-lobe) positive displacement blowers under several product lines, including the well-known Sutorbilt and Cycloblower series.

So the question “Roots blower vs. Gardner Denver blower” is really asking: should you buy a generic/OEM Roots-type blower, or a Gardner Denver branded unit specifically?

The answer depends on your performance requirements, service support needs, and whether you’re buying new or sourcing from the used equipment market.

Gardner Denver Blower Product Lines: What’s Available

Gardner Denver Sutorbilt Series

The Sutorbilt is Gardner Denver’s flagship positive displacement blower line, used across thousands of industrial installations:

• Twin-lobe design: standard Roots-type configuration
• Frame sizes: Legend, Cyclone, and other series covering flow ranges from ~40 to 15,000+ ACFM
• Pressure range: Vacuum to 15 PSIG differential (pressure); up to 15 in. Hg vacuum
• Applications: Pneumatic conveying, wastewater aeration, pulp and paper, industrial vacuum

Gardner Denver Cycloblower Series

The Cycloblower is a tri-lobe positive displacement blower offering:

• Lower pulsation vs. twin-lobe  smoother flow, reduced piping vibration
• Higher efficiency at elevated pressures  tri-lobe geometry reduces internal backflow
• Quieter operation  preferred for installations near occupied areas
• Applications: Chemical, food-grade pneumatic conveying, environmental systems

Gardner Denver Hoffman & Lamson Centrifugal Blowers

Distinct from positive displacement, Hoffman & Lamson centrifugal blowers serve high-flow, lower-pressure applications  wastewater aeration basins being a prime example.

Roots Blower vs. Gardner Denver: Head-to-Head Comparison

Bottom line: For applications where parts availability, documentation, and service support matter  and where you’re comparing used units  Gardner Denver Sutorbilt and Cycloblower units often have an advantage over generic or lesser-known Roots-type blowers.

Key Industrial Applications: Where Each Blower Type Excels

Pulp & Paper Mills

Roots/PD Blowers are used for:

• Vacuum conveying of broke and fiber
• Pneumatic conveying of pulp, additives, and chemical powders
• Aeration in effluent treatment lagoons
• Vacuum system assist in screen and cleaner systems
• Pressure rolls and felts blow-off for felt conditioning

In paper mills, blower reliability is critical. A failed aeration blower on a clarifier can create an environmental compliance issue within hours. Mills frequently maintain a spare blower unit  a quality used Gardner Denver is a common and cost-effective choice for this role.

How to Size a Roots-Type Positive Displacement Blower

Blower sizing errors are costly  an undersized blower starves the process; oversized units waste energy and wear faster. Key parameters:

1. Flow Rate (ACFM)
   Actual cubic feet per minute at inlet conditions. Always correct for altitude, temperature, and humidity standard ratings are at sea level, 68°F, 0% relative humidity.
2. Pressure Differential (PSID or in. Hg)
   The difference between discharge and inlet pressure. Positive displacement blowers are sensitive to pressure operating above the rated differential causes overheating and accelerated wear.
3. Inlet Conditions
   High altitude reduces air density, meaning a given ACFM delivers less mass flow. Factor in altitude corrections if your installation is above 1,000 ft.
4. Horsepower
   Power requirement scales with both flow and pressure. Verify motor sizing against blower curves, not just catalog ratings.
5. Discharge Temperature
   Roots-type blowers heat the air significantly at higher pressure differentials. Discharge temperatures above 250°F require attention to downstream piping and connections.

Maintenance: What Keeps a Roots Blower Running Long-Term

Whether you’re operating a Gardner Denver Sutorbilt or any other Roots-type blower, these practices extend service life:

Routine (Weekly/Monthly)

• Check inlet filter the single most common cause of premature blower wear is dirty inlet air
• Monitor outlet temperature rising temperature indicates overpressure operation or worn clearances
• Check for unusual noise or vibration gear wear and bearing wear are audible early

Annual/Major Maintenance

• Inspect and replace timing gears if backlash is excessive
• Check and set lobe-to-lobe and lobe-to-casing clearances
• Replace shaft seals if leaking oil into the air stream
• Inspect bearings  replace if wear is measurable

Common Issues and Causes

Ready to Source a Blower? Talk to a Specialist

Whether you need an urgent replacement, a standby backup unit, or are planning a system capacity upgrade, Peak Machinery can help you find the right Roots or Gardner Denver blower for your specific application.

Request a Quote Share your required flow rate, pressure, and application details, and our team will match you with the most suitable unit from our available inventory.