Go diesel for continuous, fuel-sensitive, larger jobs. Go gas for the smallest, lowest-cost, lighter, intermittent units. Small diesels under ~25 hp meet Tier 4 Final with no DPF or DEF; large Kaesers require diesel exhaust fluid.

What's the difference between a Kaeser PE and Utility model?

Same air, different mounting. PE is a tow-behind poly-canopy trailer; Utility is a compact steel skid meant to be mounted or set in place.

Buyer’s Guide · Portable Air Compressors

Size the compressor to the job, not the badge on the frame.

Q: How big a compressor do I need to run a 90-lb breaker?

Plan on a 95-110 CFM unit for a single 90-lb breaker, and step up for margin. A breaker pulls roughly 90 CFM. Running two 90-lb breakers at once needs about 180 CFM - a 175-185 CFM class machine like the CP CPS 175 or Kaeser M55 PE.

Q: Screw or reciprocating - which should I buy?

Choose by duty cycle. A rotary screw unit is rated 100% duty and runs a breaker or drill continuously all shift. A reciprocating piston unit runs about 60% duty, so it's cheaper and ideal for intermittent shop and service work but will fall behind a breaker.

Q: Do the small diesel units need DEF?

No. Units under about 25 hp meet EPA Tier 4 Final with no DPF and no SCR/DEF. Only the large 100+ hp Kaesers (M118, M125 and up) require diesel exhaust fluid.

Q: Does altitude or cold weather change how I size the machine?

Yes. Altitude cuts output about 3.5% per 1,000 ft of elevation. For cold, add an aftercooler, anti-frost valve, and cold-weather kit and check the rated cold-start temperature.

Q: What size compressor fits on a service truck?

A Vanair Viper (60-80 CFM screw) if a breaker is in the mix, or a Vanair PRO 35 (35 CFM piston) if it isn't. 25-35 CFM covers hand tools like impacts, ratchets, and tire inflation.

CFM, pressure, fuel, and mounting — the four calls that decide whether a compressor keeps your breakers, drills, and service-truck tools running all day. This guide walks every one in order.

Start with your job → Talk to an expert: 888-883-5144

Category at a glance

20–1,700CFM range

100–217PSI range

Gas / DieselEngine options

Tow / Truck / SkidMounting

Flat-Rate Shippingpriced by size

3 Brands StockedChicago Pneumatic · Kaeser · Vanair

Parts On The Shelffilters, separators, kits

Air Experts888-883-5144

Start With The Job

Start with the job, not the catalog.

A portable air compressor is a self-powered, engine-driven machine — gasoline or diesel — that makes compressed air anywhere, rated by how much air it moves (CFM) and how hard it pushes it (PSI), to run breakers, rock drills, sandblasters, and service-truck tools with no power drop in sight.

Before brand or model, answer one question: where does the air need to be? The catalog splits cleanly into two worlds, and knowing yours makes every spec below relevant instead of noise.

World 1

Air on a jobsite

A crew breaking concrete, drilling rock, or sandblasting needs a big, steady volume of air all day. That means a rotary-screw unit on a towable trailer or a set-in-place skid — Chicago Pneumatic or Kaeser Mobilair.

World 2

Air on my truck

A tech running impacts, tire tools, and the occasional breaker wants a compact unit that lives on the service body and travels call to call — a Vanair Viper truck-mount screw unit, or a Vanair reciprocating unit for lighter, intermittent work.

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Break & drill all day

One or two 90-lb breakers, sinker drills, continuous concrete and rock work.

Straight answer95–185 CFM towable/skid screw — CP CPS 110/175 or Kaeser M30/M55.

🚛

Air on my service truck

Impacts, ratchets, tires, plus an occasional breaker, mounted behind the cab.

Straight answerVanair Viper (60–80 CFM screw) if a breaker is in the mix; a PRO 35 if it isn’t.

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Shop & service, intermittent

Tire work, blow-off, impact guns — bursty air where a screw unit is overkill.

Straight answerVanair reciprocating — PRO 25 / PRO 35, or the Contractor if you also want jobsite power.

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Sandblast & multi-crew

Sandblasting or several operators tapping the same machine at once.

Straight answerBig Kaeser — M118 / M125 at 405 CFM and up; size to the nozzle.

The Buying Logic

The six decisions, in order.

Work them top to bottom. The first two size the machine; the rest fit it to your truck, your fuel, your duty cycle, and your climate.

Total CFM at the same time

Add up the CFM of every tool running simultaneously, then multiply by 1.3–1.5 for anything used continuously (grinders, sandblasting, sustained breaking). That total is your minimum CFM — the make-or-break number. Under-size it and tools slow, lose power, and the pressure sags.

90-lb breaker	~90 CFM · the classic anchor
60-lb breaker	~50–70 · mid jackhammer
Sinker rock drill	~90–110
4″ piercing/boring	~50–80
Sandblaster	50–250+ · nozzle-driven
1″ impact wrench	~10–15
1/2″ impact / ratchet	~3–6
Chipping hammer	~10–12 · continuous
Tire / blow-off	~1–2

Pressure your tools actually need

Most construction and service tools run at 90 PSI at the tool, so a 100-PSI unit is the default (the extra covers hose loss). Sandblasting and some piercing/boring tools want more. The catch: on one machine, more pressure means less air. Pick the pressure your highest-pressure tool needs, then read the CFM the machine makes at that pressure — not the headline number.

Kaeser M27	92 CFM @100 → 57 @200
Kaeser M125	405 CFM @125 → 342 @205
Viper line	80 CFM @100 → 55 @175 (across variants)

Where it lives — truck, trailer, or skid

Portability is the single biggest fork in the catalog, and it often decides the machine before CFM does. Match the mounting to how it gets to work and who owns it.

Tow it	DOT trailer — CP CPS, Kaeser PE. Biggest air, needs a hitch & a place to park.
Truck / behind cab	Vanair Viper. Frees the hitch, travels with the tech.
Set & skid	Kaeser Utility, Viper/recip skid. Most compact; you supply transport.
Tank-mounted	Vanair PRO 25/35, Contractor — self-contained air storage.

Diesel or gas

Small and truck-mounted units come in gas or diesel; everything mid-size and up is diesel. Diesel makes more torque per gallon and lasts longer under sustained load — CP cites up to 12% fuel savings in the 170–180 CFM range. Gas starts easily, costs less up front, and runs lighter. One thing to know: the small diesels (under ~25 hp) skip the DPF and DEF entirely, while the big Kaesers (M118/M125+) require diesel exhaust fluid.

Gas	Smallest, lowest-cost, lighter — M17, Viper Gas, PRO/Contractor
Small diesel	No DPF / no DEF — CP CPS/T110, Viper Diesel
Big diesel	DEF/SCR required — Kaeser M118 and up

Continuous or intermittent air

This is the “will it keep up?” question. A rotary screw unit is rated 100% duty cycle — run it wide open all shift. A reciprocating (piston) unit runs at about 60% duty, filling a tank and then resting, so it suits bursty work but will fall behind a breaker. Lead with duty cycle, not mechanism.

Duty cycle	Screw 100% vs. piston ~60%
Runs cooler	Screw 180–210°F vs. piston 300–400°F
Best fit	Screw: all-day tools · Piston: impacts, tires, blow-off
Up-front cost	Screw higher · piston lower

Climate and environment

Cold is the enemy of starting and of wet air; heat, altitude, and dust cause most nuisance shutdowns. Plan the options around where the work happens. Remember altitude thins output: engine power — and CFM — drop about 3.5% per 1,000 ft of elevation.

Cold / wet	Aftercooler, anti-frost valve, cold-weather kit; check rated cold-start temp
Hot / high / dusty	Plan for derate above ~104°F; more frequent cooler & air-filter service
Outdoors	Corrosion-coated frame; CP towables add a 110% spill-free containment base

30-galtank / skid

Best for: mechanic, lube, and service trucks — covers impacts, ratchets, and tires with the lowest cost of entry.

View product

Every Model

The full lineup, spec for spec.

CFM is free air delivery; PSI is rated / maximum working pressure. “Stocked” marks SKUs in Crowder’s current rollout; “Quote” models are cataloged and available to order. Confirm final shipping weight and price on the live product page.

Model / config	Type	CFM @100 PSI	Max PSI	Engine (hp)	Fuel (gal)	Mount	Status
Chicago Pneumatic — towable / skid diesel screw
CPS 110-100	Screw	95	100	Kubota D902 (no DPF/SCR)	7.5	Towable	Quote
T110 Utility	Screw	95	100	Kubota D902	5.3	Skid	Quote
CPS 175-100	Screw	170	100	Kubota V1505 turbo	15.8	Towable	Quote
CPS 185-100	Screw	180	100	Kohler KDI 1903 turbo	22.3	Towable	Quote
Kaeser Mobilair — towable (PE) / skid (Utility)
M17	Screw	60	100	Honda GX630 gas (17)	5	Skid	Stocked
M27 PE	Screw	92	100	Kubota D1105-B (21)	10.6	Towable	Stocked
M27 Utility	Screw	92	100	Kubota D1105-B (21)	10.6	Skid	Stocked
M30 PE	Screw	100	100	Kubota D1105-B (21)	10.6	Towable	Stocked
M30 Utility	Screw	100	100	Kubota D1105-B (21)	10.6	Skid	Stocked
M55 PE	Screw	185	100	Kubota D1803CR-T (43)	21	Towable	Stocked
M58 Utility	Screw	210	100	Kubota V2403-CR (48)	28	Skid	Stocked
M118	Screw	405	100	Deutz TCD 3.6 L4 (114)	45	Towable · DEF	Stocked
M125	Screw	405	100	Deutz TCD 4.1 L4 (121)	45	Towable · DEF	Stocked
M59 PE / M76 / M81 / M171 / M255 / M480	Screw	195–1,700	up to 217	Hatz / Deutz / Cummins	21–211	Towable · DEF	Quote
Vanair Viper — compact truck-mount screw (gas)
Viper G80 (+ C / R / CR / W)	Screw	80	100	Honda iGX800 EFI (25)	10	Truck / skid	Stocked
Viper G70 (+ C / R / CR / W)	Screw	70	125	Honda iGX800 EFI (25)	10	Truck / skid	Stocked
Viper G60 (+ C / R / CR / W)	Screw	60	150	Honda iGX800 EFI (25)	10	Truck / skid	Stocked
Viper G55	Screw	55	175	Honda iGX800 EFI (25)	10	Truck / skid	Quote
Vanair Viper — compact truck-mount screw (diesel)
Viper D80	Screw	80	100	Kubota diesel (24.8)	9	Truck / skid	Stocked
Viper D70	Screw	70	125	Kubota diesel (24.8)	9	Truck / skid	Stocked
Viper D60	Screw	60	150	Kubota diesel (24.8)	9	Truck / skid	Stocked
Vanair reciprocating — skid / tank / truck (piston)
PRO 25	Piston	25	175	Honda GX270 gas (8.4)	—	30-gal / skid	Quote
PRO 35	Piston	35	175	Honda GX390 gas (11.7)	—	30-gal / skid	Quote
Contractor	Piston	20	150	Kohler 14 / VNR680 20 gas	—	10/30-gal / skid	Quote

Don’t Forget

The compressor is half the order.

The consumables and safety gear that keep a machine — and the crew — running. Add them to the same PO and you won’t be down waiting on a filter in six months.

Maintenance kit

Separator element, air & oil filters, and belt set matched to your model. Vanair & Kaeser sell pre-boxed kits.

Browse service kits

Hose reel & air hose

The air-delivery end. Size the hose to your CFM so you don’t choke the tool at the drop.

Browse hose

FLR & tool oil

Filter-lubricator-regulator traps water and re-oils tools at the drop — good practice on any air-tool line.

Browse oil & lube

OSHA velocity fuse

Hose-break safety valve that stops dangerous hose whip. OSHA requires it on lines above 1/2″ over 40 PSI — a must on breaker hoses.

Browse accessories

Cold-weather kit

Heaters, low-temp lubricants, and freeze protection for cold-climate starting and wet-air control.

Browse accessories

Why Buy From Crowder

Machines, parts, and people who know air.

31SKUs in current rollout

4compressor families covered

3brands with parts on the shelf

1call to an air expert

Chicago PneumaticSimple, reliable towable jobsite air — 95–180 CFM, spill-free frame.Shop CP → Kaeser MobilairGerman SIGMA airend, the widest range in the catalog — 60 to 1,700 CFM.Shop Kaeser → Vanair ViperScrew duty cycle sized for a truck bed — gas & diesel, lifetime airend warranty.Shop Viper → Vanair ReciprocatingPRO 25/35 & Contractor — value piston air for service trucks.Shop Vanair →

Air compressor questions, answered.

How big a compressor do I need to run a 90-lb breaker?

Plan on a 95–110 CFM unit for a single 90-lb breaker, and step up for margin. A breaker pulls roughly 90 CFM, so a CP CPS 110, Kaeser M30, or a Vanair Viper D80/G80 covers one. Running two 90-lb breakers at once needs about 180 CFM — a 175–185 CFM class machine like the CP CPS 175 or Kaeser M55 PE, which do it with headroom.

Screw or reciprocating — which should I buy?

Choose by duty cycle. A rotary screw unit is rated 100% duty cycle and runs a breaker or drill continuously all shift; a reciprocating (piston) unit runs about 60% duty, filling a tank and resting, so it’s cheaper and perfect for intermittent shop and service work but will fall behind a breaker. If you break, drill, or sandblast all day, buy screw. If you run impacts, tires, and blow-off, a piston unit is enough.

Diesel or gas?

Go diesel for continuous, fuel-sensitive, larger jobs — more torque per gallon, longer life under sustained load, up to ~12% fuel savings in the 170–180 CFM range. Go gas for the smallest, lowest-cost, lighter, intermittent units. One important note: the small diesels (under ~25 hp) meet Tier 4 Final with no DPF and no DEF, while the large Kaesers (M118/M125 and up) require diesel exhaust fluid.

Do the small diesel units need DEF (diesel exhaust fluid)?

No — the small diesels skip DEF and the DPF entirely. Units under about 25 hp (the Kubota D902-class engines in the CP CPS 110, T110, and Vanair Viper Diesel) meet EPA Tier 4 Final with no diesel particulate filter and no SCR/DEF system, which means no fluid to buy and fewer emissions-related failures. Only the large 100+ hp Kaesers (M118, M125 and up) require DEF — budget for it as part of ownership on those.

What’s the difference between a Kaeser PE and a Utility model?

Same air, different mounting. The PE (polyethylene) version is a tow-behind trailer under a corrosion-proof poly canopy — the rental-yard, drag-to-site machine. The Utility version is a compact steel-cabinet skid meant to be mounted or set in place. An M27 PE and an M27 Utility make identical CFM; the choice is purely how it gets to and lives at the job.

Does altitude or cold weather change how I size the machine?

Yes — altitude cuts output about 3.5% per 1,000 ft of elevation, so a unit rated at sea level makes less air on a mountain grade (the Viper D70 is specifically re-rated to 100 PSI above 3,500 ft). For cold, size in an aftercooler, anti-frost valve, and a cold-weather kit, and check the rated cold-start temperature — CP’s CPS 110 and T110 start to -4°F standard, and the CPS 185 offers a pack to -13°F.

What size compressor fits on a service truck?

For a service truck, a Vanair Viper (60–80 CFM screw) if a breaker is in the mix, or a Vanair PRO 35 (35 CFM piston) if it isn’t. 25–35 CFM covers hand tools — impacts, ratchets, tire inflation. The Viper is sized specifically to fit behind the cab or in a side pack; the reciprocating PRO units are the lowest-cost option for intermittent air. Need air and jobsite power? The Vanair Contractor adds a 4.2 kW generator on the same engine.

Still not sure which machine fits your crew?

Tell us the tools you run and where the air needs to be. We’ll size it right the first time — with flat-rate shipping based on the size of the unit.

Shop all air compressors → Call 888-883-5144