An HVLP spray gun typically uses 300 to 450 L/min, as a rough guide, at a low inlet pressure, often around 2 bar. For a single painting station, a screw compressor of at least 0.6 m³/min is just enough; as soon as a prepper sands at the same time, aim for a 4-in-1 unit of 1.1 m³/min such as the K 75. What decides is not the pressure but the flow held for the whole pass.
What does HVLP change for the compressor?
HVLP stands for "high volume, low pressure". The gun atomises the paint with a large volume of air at low pressure, which cuts overspray and puts more product on the part.
For the compressor, the consequence is direct. The pressure needed is low, but the air volume is high and continuous. The classic mistake is to think "it only needs 2 bar" and buy a small compressor. It does reach 2 bar, but it cannot deliver the volume: pressure drops during the pass, atomisation turns coarse and the colour varies from one panel to the next.
Our page on compressors for body shops describes a complete workshop installation. Here we start from the gun.
Reading the gun data sheet
Three values matter in an HVLP gun manual:
- Air consumption, in L/min. This is the figure that sizes the compressor.
- Recommended inlet pressure, measured at the gun, not at the compressor outlet.
- The recommended fitting and hose diameter.
If the manual gives consumption in cfm, our flow and pressure converter turns it into L/min. Without a manual, our configurator uses 350 L/min for a paint spray gun, as a rough guide.
Step by step calculation
Take an HVLP gun whose manual states 400 L/min. It blows for the whole pass, so it counts at 100 %. The dusting blow gun, around 150 L/min, is used in bursts: it counts at 50 %, so 75 L/min.
Case 1: the painter alone.
- HVLP gun: 400 L/min.
- Blow gun: 75 L/min.
- Total: 475 L/min.
- With a 25 % margin: 475 × 1.25 = about 600 L/min.
Case 2: the painter and one prepper.
- HVLP gun: 400 L/min.
- Orbital sander: around 350 L/min, continuous.
- Blow gun: 75 L/min.
- Total: 825 L/min, so about 1,030 L/min with the margin.
Case 3: the painter and two preppers.
- HVLP gun: 400 L/min.
- Two sanders: 700 L/min.
- Blow gun: 75 L/min.
- Total: 1,175 L/min, so about 1,470 L/min with the margin.
Which compressor for each case?
- Case 1: the S 55 at its limit, the K 75 with headroom. The S 55 delivers 0.6 m³/min at 8 bar, or 600 L/min: just enough, with no margin for a second tool. It comes without a receiver or dryer, to be added. The K 75 delivers 1.1 m³/min at 8 bar with a built-in 420 L receiver, refrigerated dryer and filtration.
- Case 2: the K 75. Its 1,100 L/min cover the 1,030 L/min of the calculation, with air that is already dried.
- Case 3: the K 110. 1.7 m³/min at 8 bar, 340 L receiver, same built-in air treatment.
A piston compressor can be enough for occasional touch-ups. To paint complete panels several times a day, application is long and continuous: a screw compressor is better suited. Our article on the difference between piston and screw explains why.
Pitfalls specific to HVLP
- Setting the compressor to 2 bar. The compressor stays at its working pressure, 8 bar on these models. You regulate down at the station, with a regulator and a gauge at the gun. The receiver then stores a much larger usable volume of air.
- Hose and fittings. At 400 L/min, a hose that is too thin, a long reel or a narrow quick coupler lose pressure before the gun. Follow the diameter recommended by the gun maker and check the pressure with the trigger pulled. Our guide to connecting a compressor to the air network gives the basic rules.
- Water and oil. The gun filters nothing: whatever is in the air ends up on the paint. You need a dryer at the compressor outlet and fine filters at the paint station. See our article on fine filters. Our compressors are lubricated: the air class at the station is set with our technicians according to ISO 8573-1.
- The lubricator. No lubricator on the line feeding the gun. If some tools need one, fit it on a separate line.
To check your own case, list your tools in the configurator, or send us your gun's manual with a quote request: we will check the flow with you.
For your trade: Compressor for body shops.