Aside from the desiccant, another important part of an AIR DRYER is the oil-coalescing filter. The desiccant adsorbs the water vapour that is absorbed by the air in the air dryer. The air flow then carries away the water vapour and combines with regeneration air. As a result, a dehumidifier can remove the humidity and odours in the air.

Desiccant
A desiccant for air dryer cartridge is a small granule material that helps reduce moisture in an air system. These desiccants are similar to silica packets and remove water vapor from the air. Air dryer cartridges come in coalescing and non-coalescing styles. Coalescing air dryers contain a layered fabric pad that absorbs small amounts of oil. These oils can contaminate the system and cause excessive moisture to build up in the service tanks.

Desiccant in less expensive air dryer cartridges can degrade over time, filling downstream components and reducing the performance of the device. These types of cartridges can last for one to two years depending on the type and application. Non-coalescing air dryer cartridges can last for two to three years, although the life expectancy is shortened by other types of applications. As a result, you should check the manufacturer's recommended replacement interval to ensure a long-lasting performance.

When you remove the desiccant cartridge from an air dryer, you can use a conventional hex socket to unscrew the bolt that holds the cartridge in place. The retention bolt driving head 90 is externally accessible and has tabs 86 that prevent relative rotation between the body casting 68 and the cartridge. The bolt 84 then drops down with a snap ring 88, preventing it from falling out of the body assembly.

Oil-coalescing filter
Oil-coalescing air filters are replacing standard filter cartridges for your vehicle's heater and air conditioning systems. These advanced technology filters remove both moisture and oil aerosols from your air conditioning system's system air. As these filters use two different engineered mediums to remove these pollutants, they are more expensive to replace. Oil-coalescing cartridges also provide warranty protection and can be purchased for less than standard air dryer cartridge prices.

Coalescing air-dryer cartridges are not always better at protecting against moisture, and they may void some manufacturer warranties. They do not protect your system better against moisture, but they can keep small amounts of oil from traveling downstream. You should consider purchasing a high-quality oil-coalescing air dryer cartridge rather than a cheap, budget-friendly alternative. You can tell if your air-dryer cartridges are higher quality by looking at their desiccant content.

The air dryer cartridge reduces moisture in the air supply by absorbing the oil in the air and allowing it to dissipate. This is helpful in preventing freeze-ups during cold winter months and airline failure. Newer models of trucks use air-actuated solenoid valves for emission controls, which are more sensitive to contamination than traditional brake valves. Oil-coalescing air-dryer cartridges are designed to remove small amounts of oil and provide longer life and efficiency.

Service intervals
The air dryer cartridge replacement intervals vary depending on the type of dryer and the amount of air used in the vehicle. Drivers should monitor the quality of the air in the service tank, as excess water or oil can cause the cartridge to fail. Nagel recommends referring to the appropriate service data sheet to determine how often the cartridge should be replaced. If you use a Bendix air dryer, you can refer to their Recommended Service Intervals for Bendix air dryers.

The service intervals for air dryer cartridges depend on the manufacturer and model of your vehicle. In general, line haul operations using single trailers should replace the filter every three years or 300,000 miles. Medium-duty applications should change the cartridge every 18 months to 150,000 miles. High-air-use vehicles may need more frequent filter replacements. Checking the air brake system for moisture is another sign that it's time to replace the air dryer cartridge.