The air around us always contains water vapour. When you compress that air, its volume decreases, but the moisture content doesn’t. This increases the air’s relative humidity—and once it hits saturation point, condensation begins to form. The result? Water accumulates inside your compressed air system, especially after the compression and cooling stages.

Several factors influence how much moisture forms:

• Ambient temperature and humidity
• Compressor type and size
• Air flow rate and pressure
• Cooling stages and aftercoolers

Moisture in compressed air can lead to a long list of operational headaches—many of which come with a price tag:

• Corrosion in pipelines, valves, and tanks
• Premature failure of tools and machinery
• Inconsistent product quality in food, pharma, and electronics
• Clogging of filters and nozzles
• Freezing in outdoor lines during winter
• Microbial growth in high-moisture environments

Even if it’s not visible, excess moisture can quietly reduce system efficiency and increase energy consumption.

Water doesn’t just stay at the compressor. It shows up throughout the compressed air system, especially in:

• Receiver tanks
• Filters and dryers
• Distribution piping
• End-use tools and machines

Condensate often collects in low points and corners, which is why proper drainage and air treatment are so important.

Air dryers
Installing a compressed air dryer is the most effective way to remove water vapour from your system. There are two main types commonly used:

• Refrigerant dryers cool the air to condense and drain moisture. They are ideal for general-purpose applications and typically reach dew points around +3°C.
• Desiccant dryers use drying agents to absorb moisture from the air, allowing for much lower dew points—down to -40°C or below. These are particularly suited to critical environments or colder climates.

Condensate drains
Automated or timed condensate drains are used to remove collected liquid water from tanks, filters, and low points in the system before it can be carried further downstream.

Filtration
Although filters don’t remove water vapour, they are essential in capturing water aerosols and other contaminants that may remain after drying—providing a final line of protection for tools and processes.

Dew point monitoring
Installing a dew point sensor or meter gives you real-time insight into the air’s dryness. Monitoring dew point ensures your drying equipment is performing as expected and helps prevent moisture-related issues.