Quincy 473DS80HCB20 QT Pro — 7.5 HP, 80-Gallon Horizontal Two-Stage Air Compressor, 208V 3-Phase

The specification that matters here is not the horsepower, it is the pairing of 22.6 CFM at 175 PSI with a 100% duty cycle. Read those together and they say something specific: this machine is rated to deliver that air continuously, at the top of its pressure range, without a stated rest period. A great many compressors quote their airflow at a much lower pressure, and a duty cycle they would rather you did not ask about. This one does not need the asterisk.

It is a 7.5 HP two-stage QT Pro on a horizontal 80-gallon receiver, wired for 208V 3-Phase supply, aimed squarely at a working shop where the compressor is expected to keep up with the tools rather than the tools waiting on the compressor.

Two things to confirm before you order

Published details for this machine differ in two places, and both are worth settling before you commit.

Tank orientation. The model code, the specification block and the published dimensions — about 70" long, 23" wide and 47" tall — all describe a horizontal receiver. An earlier description on this page called it vertical. The shape of a tank decides whether it fits your building, so ask us to confirm the orientation in writing before you order and we will get it from Quincy.

Automatic drain and low-oil shutdown. Earlier copy described an automatic condensate drain and a low-oil sensor that stops the machine; the specification record gives neither — no electronic drain valve, and no pump low-oil shutdown. Plan on draining the tank manually and checking the oil yourself, and if you want an automatic drain fitted, ask — it is an add-on we can quote.

The web address of this page also carries a code that differs slightly from the model number shown in the heading, 473DS80HCB20. Match your quote against the data plate with us before you buy.

What 22.6 CFM actually buys you

Airflow, not tank size, is what decides whether a shop runs out of air. The tank is a buffer; the pump is the supply. As a rough guide, an impact wrench in intermittent use is a modest draw, a die grinder or a cut-off tool is a serious one, and a sander or a bead blaster will happily eat everything a compressor of this class produces on its own. Add up the continuous-consumption figures for the tools you genuinely expect to run at the same time rather than the tools you own, and leave headroom. If that total is close to what this machine delivers, talk to us before ordering rather than after.

The 80-gallon receiver still earns its place. It absorbs the peaks so the pump is not cycling every few seconds, it gives compressed air somewhere to sit and cool so water drops out in the tank instead of at your tool, and it means a short burst of heavy demand comes out of storage rather than out of duty cycle.

Why a horizontal tank, and what it costs

Laid down, the machine is long and low — roughly 47" to the top. That is under most shelving, under a mezzanine, under a low roof line, and out of the way of a roller-door track. It also brings the service points down to where you stand: belt guard, oil sight glass, drain and outlet are all at working height rather than over your head.

The trade is floor. A horizontal receiver takes a long, narrow strip of your building, ideally against a wall; a vertical one asks for height instead and gives the floor back. Neither layout is better in the abstract, they simply suit different buildings, and we stock this pump on both. The tank outlet is 3/4".

The pump, briefly

Two-stage compression with a finned intercooler between the stages: big cylinder, cool the air, small cylinder, 175 PSI. Both cylinders are cast iron under an aluminum head, which is the right pairing — iron for rigidity and wear where the rings run, aluminum above it to shed heat. A large balanced cast iron flywheel smooths the pulses and pulls cooling air across the pump, and the drive is by belt, so the pump turns considerably slower than the motor. Slow, heavy and cool is the whole design philosophy, and it is why these pumps are measured in tens of thousands of hours rather than in seasons.

Will it fit, and what does it need?

Allow the footprint above plus room to walk around it and to pull the belt guard. The machine weighs about 740 lbs, so it needs sound, level concrete — not an asphalt floor and not a mezzanine deck without checking the loading. Leave clear space around the pump and heads for airflow; boxing a compressor into a cupboard is the most common way people cook one.

Power. The motor is wound specifically for 208V 3-Phase and cannot be reconfigured for anything else. A magnetic starter is fitted. Quincy publishes no breaker size for this model and its own sheet says to consult a certified electrician, which is exactly our advice. Confirming your supply, providing the circuit and disconnect, and providing a floor that will take the load are the buyer's responsibility.

Perfect For

• Busy independent repair shops with three-phase service and several bays working at once.
• Body and paint shops, where continuous air at pressure is not negotiable.
• Fabrication, welding and metalwork with plasma and grinding running for long stretches.
• Fleet and municipal workshops replacing a tired single-stage unit.
• Any shop with a low ceiling or a mezzanine that rules out a vertical tank.

What is in the box

The complete compressor: two-stage cast iron QT pump with intercooler and belt guard, industrial motor, magnetic starter, oil sight glass, gauges and the 80-gallon horizontal receiver, assembled and ready to be wired and piped. Not included, and commonly assumed: air dryer, aftercooler, electronic drain valve and low-oil shutdown are all absent from this build, along with hose, piping and a regulator at the point of use.

Specifications

Certification, stated plainly

The specification sheet for this unit lists ASME on the pressure vessel and UL and CSA on the electrical components. That is a code stamp on the tank and safety marks on the electrics — two separate things, neither of which replaces the other and neither of which replaces your local inspection or your insurer's own requirements. If a particular mark or filing is a condition of your cover or your jurisdiction, verify it against the data plate before you buy. We will send you what Quincy publishes.

Warranty

The compressor carries a 1-year factory warranty, which extends to a 3-year "No Bull" warranty under Quincy's own programme. That extension has conditions attached — registration, and on several models the purchase of a maintenance kit with the machine — and we will confirm in writing exactly what applies to this model before you order, so there is no surprise at claim time. If a fault does occur, do not dismantle the pump before the claim is agreed; a stripped pump cannot be assessed.

Freight and delivery

At around 740 lbs this is a two-machine-wide pallet, not a parcel. It ships by freight on a pallet inside the lower 48 states. Have a forklift or a pallet jack ready at the delivery address, or choose terminal pickup and collect it on a trailer — plenty of buyers do, and it is often the easier option for a small shop. Residential delivery carries a residential fee. This item ships free, so there is nothing to add at checkout.

Inspect before you sign. Look over the tank, the belt guard, the motor and the pallet itself, and write any damage on the bill of lading while the driver is still there. Signing a clean receipt and finding a dent afterwards makes a carrier claim very hard to pursue.