BelAire 338HL4 7.5 HP 80-Gallon Two-Stage Air Compressor, 460V

The 338HL4 is a belt-driven machine, and on a compressor you intend to keep for a decade that is the specification worth caring about most. A belt is a deliberate weak link: it is cheap, it is stocked everywhere, it takes minutes to change, and it lets the pump turn at its own sensible speed instead of being chained to the motor's. Everything you will ever routinely touch on this compressor — the belt, the tension, the oil, the sight glass, the drain — is mechanical, visible and reachable with ordinary hand tools.

It runs on 460V 3-phase supply, drives a two-stage pump with a cast iron cylinder sleeve and aluminum heads, stores into an 80-gallon horizontal ASME receiver, and tops out at 175 PSI.

Belt drive is a design decision, not a cost saving

A direct-drive compressor bolts the pump to the motor and runs both at the motor's speed. That is compact and it has fewer parts, but it locks the pump into whatever speed the motor happens to turn, and it means a hard start is transmitted straight into the crank.

A belt lets the designer choose pulley sizes and run the pump slower than the motor. Slower means lower piston speed, cooler running, less ring and bore wear, and less noise. The belt itself also absorbs the shock of starting under load rather than passing it into the pump bearings. And when something eventually goes wrong in the drive, what fails is a belt you can buy anywhere, not a coupling that takes the machine out of service for a week.

The guard over it is fully enclosed and high flow, which is the sensible combination: fingers stay out, and the flywheel still gets to move air across the pump. Do not run this machine with that guard off, and do not block it in against a wall — the flywheel is part of the cooling system, not just a pulley.

Splash lubrication and the sight glass

The pump is oil lubricated on a splash system: dippers on the crank throw oil around the crankcase rather than pumping it through galleries under pressure. There is no oil pump to fail, no filter to change and no pressure switch to lie to you. It also means the oil level is the whole story. Too little and the dippers stop reaching, too much and the oil is churned and aerated.

That is why the sight glass matters, and why glancing at it is a daily habit rather than a service item. A low oil shut-off is not listed as fitted to this model, so nothing will stop the machine on your behalf if the level drops.

460V three-phase, on a 20 amp circuit

This unit takes 460V 3-phase supply, and BelAire's recommendation is a 20 amp breaker. For a 7.5 HP motor that is a notably modest circuit, which is what the higher supply voltage buys you: lower current for the same power, so lighter conductors and less voltage drop over a long run from the panel.

The actual amp draw is listed by BelAire as something to confirm with a certified electrician rather than published as a single figure, because it genuinely depends on your service, your run and your local code. Having that verified is the customer's responsibility and it is much cheaper to do before the machine arrives. A magnetic starter is factory fitted, so the motor has proper overload protection out of the crate. On first start, check the flywheel turns in the direction of the arrow on the guard; three-phase rotation follows the order of the supply conductors, and a pump running backwards makes noise and very little air.

Three specification conflicts we are not going to hide

Our records for this model contradict themselves in three places. Rather than publish whichever version reads better, here is exactly what we hold.

• Weight. The product overview text states 491 lbs. Our specification database records 481 lbs. The gap is small and will not change how you handle the machine, but it is a real disagreement and you should not be surprised by either number on a delivery note.
• Delivered air. The manufacturer's feature list states 18.5 CFM at 100 PSI. Our specification database and the product overview both point to 22.3 CFM, the overview giving it at 175 PSI. Those describe different pumps, not different roundings. If you are sizing this against a specific continuous-draw tool, ask us to confirm the delivered air and its rating pressure in writing before you order.
• Tank drain. One specification sheet lists an electronic drain valve as fitted; another lists it as not fitted; the manufacturer's feature list describes a manual air tank drain. Those cannot all be true. Assume you will be draining it yourself until we confirm otherwise, and ask us in writing if an automatic drain is a requirement rather than a preference.

What is not in dispute: the maximum pressure is 175 PSI and the rating pressure BelAire quotes airflow against is 100 PSI.

Will it fit?

This is a long, low machine rather than a tall one: 71" along the wall, 24" deep, 49" to the top. Give it a level, solid floor, room at the pump end for belt and oil work, and clear air around the flywheel. If your space is tight in length rather than height, ask us about the vertical-tank version instead of trying to make this one fit.

Perfect For

• Industrial buildings already running 460V distribution, where the panel space and cable cost of a bigger circuit is worth avoiding.
• Shops that service their own equipment and want a machine with no proprietary drive parts in it.
• Manufacturing and fabrication floors with steady, all-day air demand.
• Facilities with long runs from the panel to the compressor room.

In the box

• Belt-driven two-stage pump, cast iron cylinder sleeve with aluminum heads
• Aftercooler
• 80-gallon horizontal ASME tank with safety valve
• Magnetic starter, factory fitted
• Start/stop pressure switch controls
• Oil sight glass
• Fully enclosed high-flow belt guard
• Pressure gauge
• Tank drain — see the conflict note above regarding its type

Not included: an air dryer. BelAire names the CPXHT25 as the recommended dryer for this compressor and it is a separate purchase.

Specifications

Drive and pump

Motor and supply

Tank and dimensions

Certification, without the gloss

The receiver is built and stamped to the ASME pressure vessel code and carries a safety valve. That is the certification claimed for this machine and it concerns the tank.

We do not hold a North American third-party electrical safety listing issued by an accredited testing laboratory for this unit. That is a different document from a pressure vessel code stamp, assessing a different hazard, and neither implies the other. Insurers, corporate facility standards and local electrical inspectors sometimes require the electrical listing specifically. If that might apply to you, establish it and ask us in writing before you order rather than after the machine is bolted down.

Freight and receiving

Ships as freight within the lower 48 states, free of charge.

Plan how it comes off the truck before it arrives: a forklift or a dock at the delivery point, or terminal pickup if you would rather collect it. Residential delivery is available and carries a residential fee. Inspect the crate before you sign anything — skid movement, dents in the tank ends, a bent guard, oil on the deck. Write what you find onto the delivery paperwork and photograph it while the driver is present. A clean signature makes a later damage claim very hard to win.

Warranty

A 2-year bumper-to-bumper factory warranty covers all components, activated by nothing more than the purchase. Take the serial number down at uncrating and file it with the invoice.

Do not dismantle the pump, motor or pressure switch before a claim is opened. Taking a part apart to prove it failed is the surest route to losing the cover on that part. Report first, then keep to the oil interval, re-check belt tension after the first weeks of running, and drain the tank at the end of each working day while there is still pressure to push the water out.