Howden Roots Blowers in Commercial Recycling: An Equipment Buyer's FAQ

If you're responsible for equipment purchasing at a commercial recycling facility, Howden is probably on your blower spec sheets. I've been managing equipment procurement for our plant since 2021—roughly $800K in annual spend across 15 vendors, reporting to both the plant manager and finance. These are the questions I've answered most often about Howden roots blowers, including a couple I didn't see coming.

What does a Howden roots blower actually do in commercial recycling?

A Howden roots blower is a positive displacement blower. Two lobed rotors spin in opposite directions inside a tight housing, trapping a fixed volume of air and pushing it through the discharge port. The key difference from a fan: a fan accelerates air but doesn't build much pressure, while a roots blower keeps moving a steady volume of air even against downstream resistance.

In commercial recycling, that capability gets used for three main jobs. Pneumatic conveying—moving shredded plastic, paper, or light scrap through pipes. Dust collection—keeping the air breathable around sorting lines. And wastewater aeration, which often shows up in facilities with wash lines. All of these require consistent airflow at meaningful pressure, hour after hour.

We run three Howden units at our facility. Two on conveying lines, one on dust collection. They're specified for 8–12 hours daily, but they've run longer during peak seasons. No issues. That reliability is the reason the name keeps appearing on spec sheets.

Why choose Howden roots blowers over cheaper options?

Honest answer: Howden wasn't the cheapest quote we received. During our 2024 expansion, I went back and forth between Howden and a different manufacturer that came in about 30% lower. Finance liked the savings. I liked that number too, on paper.

What settled it: track record and service response. Howden has been engineering air and gas handling equipment since 1854. Their roots blowers are installed in thousands of industrial applications, which means the design bugs were shaken out long ago. I'd rather buy equipment with that history behind it than take a chance on a newcomer's spec sheet.

The service factor showed up quickly. We had a bearing failure on one unit at 23 months—covered under warranty, replacement part shipped same-day. On a Saturday. The vendor picked up on the second ring. That kind of backup isn't on any spec sheet, but it's a huge part of total cost of ownership. Cheap equipment only saves money if it never fails.

Can a Dewalt blower or backpack leaf blower replace a roots blower?

I get asked this at least twice a year, usually by someone who sees the price of a Howden unit next to a $200 backpack leaf blower. Short answer: no. Not even close.

A Dewalt blower or a backpack leaf blower is a centrifugal fan. It moves a high volume of air at low pressure—measured in inches of water column. It's designed for short bursts of work: clearing leaves, blowing dust off a floor. Run one for eight hours straight and you'll cook the motor.

A roots blower is a different category of machine. Machined rotors, tight clearances, industrial bearings, forced lubrication. Its pressure is measured in PSIG, which is orders of magnitude higher than any leaf blower can produce. And it's designed for continuous duty—24/7 operation, day after day.

Put simply: a leaf blower is a bicycle. A roots blower is a dump truck. They both move air, but the resemblance ends there.

What specs actually matter when buying a roots blower?

Core specs are straightforward: air volume in CFM, pressure in PSIG, motor power in HP, and noise level. Every manufacturer publishes those clearly. The specs that cause trouble are the ones in the fine print.

We didn't have a formal specification review process when we bought our first roots blower. Cost us later when a rush order arrived without an agreed delivery window—the invoice included an unauthorized fee. After that, I built a checklist I now use for every major purchase:

• Required CFM at the actual system backpressure, not just at open discharge
• Expected duty cycle—8 hours a day or 24/7? It changes the spec completely
• Ambient conditions—dusty, hot, or humid environments affect cooling and filtration needs
• Service interval requirements—is the maintenance team able to keep up?
• Spare parts lead times—ask for actual recent data, not promises

That last point is the one I wish someone had pushed on me earlier. Even an excellent blower is a bad purchase if parts take six weeks to arrive when it's down.

How much maintenance does a Howden roots blower actually need?

Less than you might expect, more than you can ignore. Our mechanics spend maybe an hour per week checking all three units: oil levels, air filters, belt tension. Routine stuff.

Major service on our units comes around 8,000 running hours—roughly a year of single-shift operation. The exact interval depends on model and operating conditions. As of January 2025, that's what Howden's documentation recommends for our environment. Check your manual, not a blog.

Here's the part I'll be direct about: oil changes are non-negotiable. The rotor clearances in a roots blower are measured in thousandths of an inch—or rather, fractions of a millimeter, depending on the unit. Contaminated oil scores the rotors, clearances open up, and performance drops fast. I've seen a blower destroyed in under a year by deferred oil changes. That wasn't a Howden, but positive displacement machines all follow the same physics.

A scheduled PM program isn't a cost center. It's insurance against a mid-five-figure replacement.

Do Howden roots blowers use a lot of electricity?

Depends on how you size them. An oversized blower running at partial load wastes energy. A properly sized unit running near its design point is more efficient than most people expect.

One pattern I've noticed: facilities install a big blower to cover a worst-case scenario, then throttle it with a bypass valve for normal operation. That's pure waste. We fixed this on our dust collection line by installing a variable speed drive unit. It matches airflow to actual demand, and our electricity use for that system dropped by about a fifth (note to self: I still need to pull the exact energy audit numbers—this is close, but I want to verify).

If energy efficiency matters for your project, ask the manufacturer's applications engineers about proper sizing and variable speed options. Don't just buy the biggest unit on the price sheet. The fundamentals of how a roots blower works haven't changed in a century—but the way we control them has, and that's where the savings are.

Can a Nest thermostat replace heating and air conditioning?

This question has nothing to do with blowers, but like clockwork, I'm asked it every winter. The answer is no. A Nest thermostat is a smart controller. It replaces the thermostat on your wall—not the furnace, not the air conditioner.

What a Nest does well: scheduling, remote control, energy tracking. It tells your existing heating and air conditioning equipment when to run. What it cannot do is generate heat or cold air. If your furnace or AC hardware is dead, a Nest won't bring it back to life. It will just give you a smarter way to control a system that still needs to physically exist.

We installed Nests in our office during the 2022 renovation. But we also replaced two furnaces that same year, because no thermostat—smart or otherwise—can fix a 20-year-old heat exchanger.

A thermostat is the brain. The furnace and AC are the lungs. You need both. No smart device replaces the other part.