How to use an oil-free air compressor
Updated: 21.10.2026
The box is in the garage, the pump says oil-free, and you are about to plug it into a 230 V socket. Oil-free means you do not fill a sump. It does not mean you skip the drain, the regulator or the coupling. This is how to use an oil-free air compressor on the first afternoon, from the listings in our [oil-free air compressor comparison](/hub/compressors/air-compressor-oil-free), HSE guidance on receivers, and the faults reviewers reported. The Products Compared editorial team did not run these machines in a lab. A qualifying purchase can earn a commission at no extra cost to you.
The box is in the garage, the pump says oil-free, and you are about to plug it into a 230 V socket. Oil-free means you do not fill a sump. It does not mean you skip the drain, the regulator or the coupling.
The box is in the garage, the pump says oil-free, and you are about to plug it into a 230 V socket. Oil-free means you do not fill a sump. It does not mean you skip the drain, the regulator or the coupling. This is how to use an oil-free air compressor on the first afternoon, from the listings in our oil-free air compressor comparison, HSE guidance on receivers, and the faults reviewers reported. The Products Compared editorial team did not run these machines in a lab. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Drain or trap | Outlet | Day-one check | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Hyundai Hyundai HY7524X 24 L | Condensation trap | Euro quick | Grit reported; lead about 1 m | 9.2 | about £149.95 | View offer |
| Preis-Tipp |  Bimson Power Bimson Power 8 L | Check for a leak | Not stated | Valve direction disputed | 9.0 | about £99.99 | View offer |
| Alternative |  Einhell Einhell TC-AC 240/50/10 OF | Receiver drain | Quick-release | Burning smell reported | 8.6 | about £212.95 | View offer |
On this page
What you do not have to do
You do not add oil before the first start. The listings in this set describe oil-free pumps, and none includes an oil bottle. Pouring oil into a pump with no sump wrecks it. You also skip the daily oil check. You still have water. Moisture drops out in the tank and the hose. A condensation trap or a drain cock is that water, not an optional extra. The air is not breathing air. Look before you switch on. Hyundai 24 litre reviewers found grit in a new tank. One HYCHIKA smoked on day one. One Einhell 50 litre arrived with a burning smell.
First start and the drain
Stand the compressor on a firm floor, fit the wheels or feet the manual shows, and keep the outlet closed. Use a wall socket, not a coiled extension lead. Both Hyundais are listed at up to 13 A, and a coiled lead heats up and drops voltage. Reviews describe the Hyundai 24 litre lead as about 1 metre, so the socket has to be close. If the plug is the ABAC’s Type G adaptor, seat it fully. Switch on and let the pump stop on its pressure switch. You should hear it cut out. You should not smell burning or see smoke. If you do, unplug it and do not restart it.
Drain after use, before you put it away. Switch off and unplug. Let it cool. Wear eye protection. Open the low-point drain slowly, jet aimed at the floor and away from skin. Close the drain. Do not empty the tank through the safety valve. Toolden notes that Hyundai removed the pull ring on the HY7524 so people would not dump air that way. The drain cock is the drain. If the safety valve sticks or will not reseat, stop using the machine.
Regulator, Euro coupling and the plug
Tank pressure and tool pressure are different needles. On the Hyundai 24 litre, reviewers saw cut-out nearer 7 bar than the 8 bar title. Set the regulator to the tool, often well below cut-out, and read the outlet gauge. A nailer fed the full tank will misbehave. Most outlets here are Euro quick couplings. The Draper title says a Euro outlet, and reviews say there is no hose. The Hyundai 24 litre includes the compressor and a manual. A different nailer profile will not latch. One Bimson review said the valve instructions reversed clockwise and anticlockwise. Test the fitting with the tank only partly filled. The buying guide is where that coupling is a buying choice. Do not cut a moulded plug off and then expect a free replacement. One Einhell 50 litre reviewer did that and was refused. If a UK order arrives with a non-BS 1363 plug, as in one Einhell silent report of an EU-spec unit, stop and sort the plug.
Stop and unplug
Unplug anything that smokes or smells of burning. That is a HYCHIKA on day one and an Einhell 50 litre returned after a day. It is not a running-in smell. A leak that empties the tank, as on one Bimson 24 litre, makes the motor run the duty the tank was meant to avoid. Switch off and find the fitting.
A competent person, not another weekend, is the next step when the receiver is work equipment at or above 250 bar litres. Fifty litres at 10 bar is 500. A 24 litre tank at 8 bar is 192, under the written-scheme exemption in the Pressure Systems Safety Regulations 2000. Also stop if the shell is badly rusted or dented, or the safety valve will not reseat. Paint, and why you do not add an oiler, is on the spray painting page.
Common questions
Do I add oil before the first start?
No. These pumps are sold as oil-free, and the boxes do not include oil. Adding oil where there is no sump damages the pump. You still drain water after use. If a title says lubricated, or the specification prints an oil capacity, it is a different machine and this do-not-add-oil line does not apply.
How do I drain the tank without spraying myself?
Switch off, unplug, and let it cool. Wear eye protection. Open the low-point drain slowly, with the jet on the floor and away from skin. Close it when the water stops, and check for a hiss on the next start. Do not use the safety valve as the drain. Tilt only if the manual says an upright tank will not empty.
Should I pull the safety-valve ring?
Not to empty the tank. The drain cock is for condensate. The safety valve is there if the pressure switch fails. Hyundai’s retailer notes that the HY7524 pull ring was removed so people would not dump tank air through it. If a valve sticks open or will not reseat, unplug the compressor and leave it unused.
Why will my air tool not click on?
The coupling often does not match, or the regulator is shut. Most of these machines use a Euro coupling, and several include no hose. Check the outlet gauge, not only the tank gauge, and set the tool’s pressure. Confirm the drain is closed, or the pump will run and the tool will still see nothing.
The motor smoked. What now?
Unplug it and leave it unplugged. Do not restart it to see if the smell goes. Day-one smoke is in the HYCHIKA reviews, and a burning plastic smell is in the Einhell 50 litre reviews. Contact the seller once the machine is cold. A burning smell is not an oil-free pump bedding in, and oil will not cure it.
Why is there grit in a new tank?
Manufacturing residue. Hyundai 24 litre reviewers heard shot or grit when they rocked an empty tank. Let the first drain run that grit clear before you paint or use an airbrush, with the jet pointed away from you. If the shell is dented, or the grit is rust scale rather than factory shot, stop and have the receiver checked.
Related pages
Sources
Public UK sources and manufacturer pages below. amazon.co.uk listings checked on 19 October 2026.
- Pressure Systems Safety Regulations 2000 (retrieved 19 October 2026)
- HSE INDG178: written schemes of examination (retrieved 19 October 2026)
- Control of Noise at Work Regulations 2005 (retrieved 19 October 2026)
- HSE INDG362: noise at work (retrieved 19 October 2026)
- Electrical Equipment (Safety) Regulations 2016, regulation 35 (retrieved 19 October 2026)
- ABAC UK: small air compressor buying guide (retrieved 19 October 2026)
- Sealey HVLP01 instructions (retrieved 19 October 2026)
- Anglian Compressors: breathing air quality (retrieved 19 October 2026)