Quincy 4152021984 QGS 15 HP 120 Gallon Rotary Screw Air Compressor with Dryer

The feature on this machine worth understanding before any of the others is Auto-Dual operation. It lets you programme a timed shutdown — the compressor stays available while the shop is working and takes itself out of standby when nothing is drawing air. On a unit rated for 100% duty that sounds like a contradiction, and it is exactly the point: a screw compressor is designed to run, so left alone it will happily idle through the night maintaining pressure in a system nobody is using.

Idle running is the quiet cost of owning a rotary screw. The machine is not doing anything wrong, it is doing what it was built to do, and the meter turns anyway. Auto-Dual is the answer to that: run continuously when the work is there, stop cleanly when it is not, and start again on schedule. It is one of the few compressor features that pays for itself in electricity rather than in convenience.

54.9 CFM at 125 PSI, and what that actually covers

This unit delivers 54.9 CFM at 125 PSI. That is enough to keep several technicians working without anybody waiting on pressure: impact wrenches, ratchets, air hammers and blow guns running together, with headroom for a sander or a small blast cabinet. It is the range where a shop stops planning its day around the compressor's recovery time.

The delivery is continuous rather than peak. That distinction is the whole reason to move up from a reciprocating machine: a piston compressor's rated output assumes it gets to stop and cool, and a full afternoon of demand will find the limit of that assumption. A 100% duty screw element holds its output for as long as you ask it to.

The dryer is carrying the moisture load on its own

An integrated refrigerated dryer is fitted, and the manufacturer's data agrees on that across the title, the feature list and the specification table. It condenses moisture, oil mist and debris out of the air before it reaches your pipework, which is what protects tools and finishes downstream.

One detail from the specification table worth flagging, because it is unusual: this model records no aftercooler. On many packaged compressors an aftercooler drops the discharge temperature and removes the bulk water first, leaving the refrigerated dryer to handle the remainder. Here the dryer is doing all of that work. In practice that means two things. Your dryer is the single point of moisture control, so keeping its condenser clean matters more than it would on a two-stage arrangement; and if your air quality requirement is demanding — instrument air, certain finishing work — it is worth a conversation with us about your dewpoint target before you order rather than after.

Long-life V-belt drive and the rest of the mechanicals

Power reaches the airend through a long-life V-belt drive. Belts are a serviceable wear item and this one is specified for extended life, which trades a periodic tension check against a transmission that is inexpensive and straightforward to work on. Lubrication is premium synthetic rated for 8,000 hours, keeping oil carryover low and stretching the interval between fluid services considerably. The motor is a TEFC design, the enclosure is Quincy's standard quiet cabinet, low-oil shutdown covers engine and pump, and there is an oil sight glass for the routine check.

Will it fit, and can your supply carry it?

The package is 76 inches long, 25 inches wide and 58 inches tall, and weighs 980 lbs. Note the proportions: this is the low, long configuration — a horizontal 120 gallon receiver with the compressor and dryer sitting on top of it. At 25 inches wide it slides into places a taller cabinet will not, but you will need the full 76 inches of run plus service clearance at the panel end. The tank outlet is 1/2-inch, which is where your header sizing starts.

On power: this is a 208-230/460V 3-phase machine with a magnetic starter fitted, and it needs a licensed electrician. Quincy publishes neither an amp draw nor a recommended breaker size for it — both entries in the manufacturer's data read "Consult Certified Electrician" — and we will not invent figures they chose not to print. Get the service, feeder and disconnect sized against the nameplate before delivery. Electrical supply, siting and any permits are the customer's responsibility.

Perfect for

Independent automotive shops of three or four bays running tools continuously. Fabrication and welding shops needing dry air for plasma cutting. Cabinet and woodworking shops where moisture in the line ruins finishes. Any operation with long quiet periods that would benefit from a compressor which shuts itself down rather than idling through them. Three-phase supply is required.

Specifications

The sound level is missing from that table on purpose. This product's data holds a noise figure with no unit recorded against it, and a bare number is not a specification worth publishing on a machine you may have to work next to. Ask us and we will quote it from the current Quincy datasheet.

What's included

Per the manufacturer's feature list and specification table: the QGS rotary screw compressor with long-life V-belt drive, the integrated refrigerated air dryer, the 120 gallon horizontal receiver, the TEFC electric motor, the standard quiet enclosure, Auto-Dual control, an air filter, an oil sight glass, low-oil shutdown on engine and pump, and premium synthetic lubrication factory filled. An electronic drain valve is not included. Note also that unlike several models in this range, a pressure gauge is not listed in this unit's specification table — if you need one at the receiver, ask us before ordering.

Shipping and delivery

This compressor travels as freight to the lower 48 states, and the freight charge is worked out live at checkout for your own delivery address rather than printed here where it would go stale. Nearly half a ton on a long crate means the unload is your side of the job: a dock, a forklift, or collection from the carrier's terminal. Residential addresses carry a residential fee. When it arrives, walk around the crate and look at the base rails and the cabinet corners before you sign anything, and write whatever you find on the bill of lading — a clean signature closes the door on a freight damage claim.

Warranty

Recorded standard cover is 1 Year consumer and 1 Year commercial. An extended 3 Year factory warranty is available to purchase, and the True Blue 5-Year warranty applies where a Quincy authorized start-up commissions the machine — that commissioning is a condition of the longer cover, not an optional extra, so build it into the install. If you suspect a warranty fault, shut the compressor down and call us before anybody opens it up. Diagnosis by disassembly is the fastest way to turn a covered repair into an uncovered one.