BelAire QP318VE: the quiet-series compressor whose circuit size is actually published

Buying a stationary compressor usually means buying it first and finding out what it needs afterwards. Most spec sheets in this class decline to name a breaker size and refer you to an electrician, which is prudent for the manufacturer and unhelpful if you are trying to work out whether your panel has room before you spend the money.

BelAire publish a figure for this one. The QP318VE is specified with a 40 Amp Breaker on 208-230V, 1-Phase supply. That single number turns an unknown into a planning exercise you can do at the panel with a torch, before anything is ordered.

The machine itself is a 5-HP two-stage cast iron piston compressor inside a sound enclosure, rated at 66 dBA, on an 80-Gallon vertical ASME tank with a 175 PSI ceiling.

Can your panel take it? Work through this before you order

• Supply. 208-230V, 1-Phase. Check the voltage at your panel, not on a neighbouring machine's plate.
• Circuit. A 40 Amp Breaker is the manufacturer's stated recommendation, on a dedicated circuit. Conductor sizing depends on the run length and is your electrician's decision, but the breaker figure tells you immediately whether the panel has the capacity and a free double slot.
• Starter. A magnetic starter is included with the compressor, so overload protection for the motor comes in the crate rather than on a separate order line.
• Permits. Most jurisdictions want the circuit inspected. Factor the timeline in.

The electrical installation, the site and any permits remain the customer's responsibility. We will confirm any published figure against BelAire's documentation if you ask before ordering.

Right-sized, not undersized

There is a habit of buying the largest compressor a budget allows. It is worth resisting. A larger motor needs a larger circuit, and if the shop's demand does not justify it the machine spends its life cycling — which is harder on a pump than running under load.

A 5-HP two-stage machine on an 80-Gallon reserve is sized for a one or two-bay shop, a serious home workshop or a light production bench: impact tools, air ratchets, blow-off, a plasma cutter, intermittent spray work. The 80-Gallon tank does much of the work here — a large reserve means short demands are met from stored air rather than by starting the motor, which is exactly the duty a piston compressor prefers.

Two stages, cast iron, and a shroud around it

Two-stage compression is why this machine reaches 175 PSI without running its pump hot: air is compressed, cooled, then compressed again in a smaller cylinder. The integrated aftercooler downstream drops the discharge temperature further, and cooler air carries less water — which is the difference between dry air at the tool and rust in your lines.

The cylinder is cast iron, chosen because iron holds its bore under sustained heat. Lighter cylinder materials distort, and a distorted bore is a pump that starts consuming oil and losing pressure.

The whole pump sits inside a high-strength ABS enclosure with a high-flow fan, which is what produces the 66 dBA rating. That enclosure carries an obligation: it only works if air can move through it. Do not stack stock against the grilles, do not tuck it into a sealed cupboard, and do not run it with panels removed. The fan, ducting and panels are one cooling system, and defeating any part of it is how an enclosed compressor overheats.

The two things watching it when you are not

Because the pump is behind panels, the usual early warnings — a change in sound, a visible oil level, heat you can feel — are muted. Two automatic protections cover that gap. Low oil level protection shuts the machine down before a starved pump seizes. High temperature shutdown does the same if cooling is compromised, which on an enclosed machine is the most likely way trouble starts. An oil sight glass lets you check the level without dismantling anything.

Perfect For

• One and two-bay service shops. Enough air for the work, on a circuit an ordinary panel can supply.
• Home and hobby workshops with real tools. The 40 Amp figure is what makes this plannable at home.
• Attached and shared buildings. 66 dBA is the reason to choose the enclosed version.
• Anyone whose panel will not carry a bigger motor. Right-sizing beats an oversized machine you cannot feed.
• Tight floor plans. A vertical tank on a 38.2" by 24.3" footprint.

What's in the Box

• 5-HP single-phase 208-230V motor with magnetic starter included
• Two-stage cast iron pump, belt driven, splash lubricated
• High-strength ABS sound enclosure with high-flow fan
• 80-Gallon ASME certified vertical air tank, 100% factory tested at full pressure
• ASME safety valves and an integrated aftercooler
• Automatic pressurised tank drain — a pressurised drain, not an electronic one
• Low oil level protection and high temperature shutdown
• Oil sight glass and pressure gauge
• 3/4" tank outlet
• Shipped "wet", oil filled and ready to use

An air dryer is not included and is not fitted.

Specifications

One specification we are leaving blank on purpose. The delivered air volume for this model is recorded in the product data as a bare number with no unit against it, and we will not restate a figure whose units the data does not establish — the risk of publishing a wrong flow rate is worse than the inconvenience of omitting it. If air delivery is what your decision turns on, ask us in writing and we will get it confirmed by BelAire before you order.

Certification, stated honestly

This compressor's data records ASME certification, and that covers the part where it counts most: the tank is an ASME certified pressure vessel and the relief devices are ASME safety valves.

It does not record any listing by an independent testing laboratory for the electrical assembly taken as a whole. That is a different approval, granted by a different body, and a tank rating is not a substitute for it. Insurers, workplace safety schemes and local electrical inspectors sometimes require one for equipment in a commercial building — in a private garage it usually makes no difference at all. Find out which case you are in before you buy, not on inspection day.

Shipping and delivery

Shipped freight to the lower 48 states, free of charge. Sort the unload before delivery: a forklift, a loading dock, or collecting it from the freight terminal yourself. A residential delivery adds a fee, which is applied and shown at checkout. Inspect the crate at the kerb and note any damage on the bill of lading with the driver present — signing clean and reporting damage afterwards leaves you with almost no leverage.

Warranty

A 2 Year consumer warranty is recorded against this model; the warranty document linked on this page is the version that governs. Whatever it covers, do not compromise it: if something fails, photograph the fault where it sits, leave the assembly whole, and contact us before a spanner goes near it. Taking a component apart ahead of assessment is the quickest way to turn a covered failure into an uncovered one.