DeWalt 2-Stage Electric Air Compressor (120 gal)

Why I chose the DeWalt 120‑gal two‑stage for my shop

I needed a central air source that could support a mix of high‑demand tools without babying the throttle: paint guns, a small blast cabinet, die grinders, a plasma table, and general shop air. After living with the DeWalt 120‑gal two‑stage for months, I’m confident saying it’s a serious shop compressor that rewards a proper installation with steady output and predictable behavior. It’s not a budget unit and it’s not for single‑phase garages, but in the right setting it’s a workhorse you don’t have to think about much.

Build and design

This is a conventional, heavy‑duty, belt‑drive, oil‑lubricated, two‑stage setup with a 10 HP, 230 V, 3‑phase motor and a 120‑gallon ASME horizontal tank rated to 175 PSI. The pump is cast iron with splash lubrication, an extra‑capacity oil sump, and a finned copper intercooler between stages. The cooling package is better than average for this class: a balanced flywheel and a large glass‑filled composite fan behind a metal belt guard that actually moves air rather than just meeting a safety requirement.

The motor spins at 1750 RPM (4‑pole), and the unit ships with a pre‑wired magnetic starter. That last detail matters—it shortens electrical work and ensures the motor sees the inrush protection it needs. The tank has a 3/4‑inch outlet, which is appropriate for the airflow the pump can deliver.

On paper, it’s rated 35.0 CFM at 100 PSI and 33.6 CFM at 175 PSI. In practice, those numbers felt honest in my use. With the pressure switch set to cycle between roughly 145 and 175 PSI, it kept up with two simultaneous grinders and intermittent plasma cutting without chasing its tail.

Installation notes from the shop floor

At 60 x 75 x 29 inches and roughly 920 pounds, this is not a one‑person install. Plan on a forklift or stout pallet jack. I placed it on vibration isolation pads and anchored it with 3/8‑inch concrete anchors. The manual doesn’t demand pads, but they reduce structure‑borne noise and keep the tank from walking when the pump cycles.

A few setup suggestions based on what worked well:

• Use a short flex hose or stainless braided connector from the tank outlet to your hard piping to isolate vibration.
• Step up to a 1‑inch main header if you’re feeding several drops. Keep runs short and avoid sharp tees near the compressor outlet to minimize pressure drop.
• Provide ventilation. The cooling fan pushes a lot of air; don’t box it in. If you build an outdoor or remote shed, include intake louvers and a thermostatically controlled exhaust fan.
• Budget time for electrical. It’s 3‑phase, full load at 28 amps, with a recommended 35‑amp breaker. I used a local lockable disconnect and appropriately sized THHN to the starter.

It took part of an afternoon to position, anchor, run the disconnect, land conductors in the starter, and plumb the header with a drip leg and filter/regulator/dryer bank.

Performance and air delivery

What matters with a shop compressor is not just peak CFM but how it behaves across a workday. Here, the DeWalt’s two‑stage pump and large reservoir make a good combination.

• Recovery: From a cut‑in around 145 PSI to 175 PSI, recovery times were consistent and brisk for the size. It doesn’t feel strained near the top of the range.
• Stability under load: With a blast cabinet (modest nozzle) and a DA sander going, line pressure at the end of a 1‑inch header stayed above 110 PSI regulated without the compressor falling behind.
• Heat management: The finned copper intercooler and the big fan keep discharge lines hot but not scorching. Head temps settle quickly during off cycles, which bodes well for valve and ring life.

If your workflow is truly continuous at high flow—think wide‑open blasting for hours—a rotary screw is the right tool. For mixed‑duty fabrication, collision repair, woodworking with HVLP finishing, and general industrial maintenance, this machine has the lungs.

Noise and vibration

DeWalt lists 84 dB(A). By ear and a quick meter check at about three feet, that’s in the ballpark. It’s quiet for a 10 HP reciprocating compressor, but it’s still a 10 HP reciprocating compressor. In a shared work area, remote mounting or an insulated utility room makes life nicer. The balanced flywheel keeps vibration reasonable; on pads and anchors, it’s well mannered.

Maintenance and serviceability

One of the reasons I like this unit is that basic maintenance isn’t a fight:

• Oil sight glass is large and easy to read.
• Drain, filters, and safety valve are accessible without gymnastics.
• Belt tension checks are straightforward behind the metal guard.

It’s a splash‑lubed pump, so use the correct compressor oil and keep intervals consistent. The extra‑capacity sump helps oil temps, and I saw slower oil darkening than on smaller shop units. Still, don’t stretch changes; reciprocating compressors are unforgiving of neglect.

Two omissions to note: there’s no electronic auto drain and no low‑oil shutoff. I added an automatic drain to the tank and installed a timed solenoid on my prefilter drip leg—money well spent.

Air quality and moisture management

The built‑in intercooler knocks down some water, but you’ll still get plenty of condensate at the tank. If you’re painting or plasma cutting, plan for:

• A particulate/coalescing filter pair and a dryer (refrigerated or desiccant) downstream.
• Sloped hard lines with drop legs and drains at each station.
• An auto drain on the tank, or a disciplined manual drain routine at the start and end of the day.

With a refrigerated dryer and appropriately sized filtration, I had no moisture issues in the paint booth or with CNC pneumatics.

Electrical and controls

The pre‑wired magnetic starter is a standout convenience and adds protection for the motor. The pressure switch is set conservatively for a 175 PSI max tank. Controls are basic and industrial—no gimmicks, no touchscreens. For most shops, that’s a feature, not a bug. If you need remote start/stop or building management integration, you’ll need to add it.

What I’d improve

No machine is perfect. A few items I’d change or budget for:

• Include an automatic tank drain from the factory.
• Offer an optional low‑oil shutdown kit for splash‑lubed pumps.
• Provide a short flexible connector in the crate for the 3/4‑inch outlet to discourage rigid coupling right off the tank.
• A clearer, large‑format sticker with torque specs and maintenance intervals near the sight glass would be handy.

None of these are deal‑breakers, but they’re quality‑of‑life improvements competitors sometimes include.

Who it’s for

• Best fit: Small to mid‑size fabrication shops, collision centers, cabinet shops with finishing, maintenance departments—anywhere multiple stations need reliable, high‑pressure air throughout the day.
• Maybe not: Single‑phase garages (this is 3‑phase only) and operations needing true continuous high‑CFM duty for hours on end—consider a screw compressor there.

Reliability and warranty

Across months of daily use, the compressor has been uneventful—which is exactly what I want. Starts are clean through the magnetic starter, pressure holds, and there’s no mystery oil consumption. The listed warranty is two years on the pump and one year on other parts; keep installation and maintenance records to make any claims straightforward.

Bottom line

The DeWalt 120‑gal two‑stage is a thoughtfully built, industrial‑leaning reciprocating compressor with honest airflow, solid cooling, and a starter package that makes integration easier. It asks for proper planning—3‑phase power, a real foundation, good ventilation, and a moisture strategy—but it pays that back with dependable performance across varied shop tasks.

Recommendation: I recommend this compressor for shops that need around 30–35 CFM at working pressure with headroom, prefer simple and serviceable components, and have 3‑phase power on tap. It’s not the quietest or the most feature‑rich, and you’ll want to add an auto drain and good filtration, but the core—pump, motor, tank, and cooling—feels robust. If that aligns with your workload and infrastructure, it’s an easy choice to live with.