Using air compressors in humid environments

SIP Maxi 12 Regulator SIP Maxi 12 Regulator

Humidity is always present in the atmosphere to some extent, but when using air compressors in humid environments, it can become problematic.

What happens to humid air in an air compressor?

When you compress humid air, the water vapour can condense into liquid water inside the air compressor – a process similar to squeezing liquid water out of a sponge. Water condensate in the compressor can become contaminated by other condensates, for example by lubricating oil, making it more difficult to dispose of in line with environmental legislation.

But the problem does not end there – compressing air initially heats it up, and this can allow more water to remain in the compressed air as vapour. During its journey along your compressed airline to the point of use, it’s normal for the compressed air to cool back down, causing even more water vapour to condense inside the airline.

This can leave pools of water condensates at low points inside the airline, partially or completely blocking the line and affecting efficiency, or leading to ‘wet’ air coming out at the end of the hose.

So what’s the solution?

For condensates that form in the air compressor itself, condensate separators use various filtration methods to extract the oil and leave only clean water that can be disposed of as any other non-harmful wastewater.

Air dryers tackle the problem of water condensate deep in the machine by drying the compressed air at a designated point along the line, so that the air travelling along the hose is already at lower humidity. All this allows you to demonstrate that you comply with the 1991 Water Resources Act, which requires businesses to take mitigating action against water pollution.

You may also be able to mitigate the effects of atmospheric humidity by placing your air compressor in a well ventilated location or dehumidifying the space around it and its intake. However, it is still essential to have a method to extract and treat condensates from the compressor and airline.


This not only complies with environmental legislation and helps to keep your air compressor and hose in good condition for longer, it also maximises the efficiency of your system as a whole, giving you dry compressed air with less power consumption.

At Ace Compressors, we have a team of experts who will be able to advise you on the best solutions to your air compressor issues. Get in touch with us today to see how we can help you.