Simple Advice & Troubleshooting on Desiccant Dryer Maintenance

This blog post was written by Charles Eskrigge—sales manager at Air & Vacuum Process, Inc - AVP - in Texas. 

Just like neglecting routine car maintenance can lead to costly repairs, overlooking preventive maintenance on regenerative desiccant compressed air dryers can cause significant issues, ranging from equipment damage to costly downtime.

Keeping your air dryer in top shape requires regular attention to prevent malfunctions that could lead to contamination, expensive repairs, and production delays.

Here’s how to ensure your desiccant air dryer runs efficiently and reliably in 2024.

Why Regular Maintenance is Crucial

Desiccant dryers are vital for maintaining clean, dry compressed air in many industrial applications. However, without regular maintenance, these systems can suffer from wear and tear that may not be immediately noticeable. 

By the time a failure occurs, water, oil, or desiccant dust may have already migrated downstream, potentially causing damage to sensitive equipment or contaminating products.

Routine maintenance not only extends the lifespan of your dryer but also ensures optimal performance, minimizes energy consumption, and prevents the need for costly emergency repairs or rental equipment.

View all desiccant compressed air dryers

Start with the Filters

Pre-Filters

The pre-filter is critical for protecting your dryer’s desiccant and components from contaminants like compressor oil, condensed water, and particulates. In heat-regenerated dryers, compressor oil can even pose a fire hazard. 

A differential pressure gauge or indicator shows when it’s time to change the filter elements, typically every 6 to 12 months. Regular inspections and timely replacements of filter elements are essential for preventing contaminants from reaching the desiccant.

Automatic Drain Valves

Coalesced liquids accumulate in the pre-filter sump and must be regularly drained. If the automatic drain valve fails or if a manual drain is neglected, contaminants can spill into the dryer, damaging the desiccant and components. Inspect and test drain valves regularly, and repair or replace them as needed.

After-Filters

Every dryer should have a particulate after-filter to prevent desiccant dust from migrating downstream. As with pre-filters, change out the filter elements based on a differential pressure indicator or schedule replacements every 6 to 12 months.

Regenerative Desiccant Dryers Maintenance Tips

Control Air Filters

These filters protect critical components like switching valves and solenoid valves from desiccant dust. Since the switching valve is one of the most expensive components in the dryer, maintaining the control air filter is a wise investment. Replace the control air filter element alongside pre-filter and after-filter elements to ensure comprehensive protection.

Inspect and Maintain Control Valves

Regenerative desiccant dryers rely on various control valves, including inlet switching valves, purge exhaust valves, check valves, and solenoid valves. These valves should be cleaned and inspected annually, with worn or damaged parts replaced as necessary. Repair kits are available for most valves, offering a cost-effective way to maintain their performance.

Purge Settings

The purge adjusting valve or purge pressure should be checked periodically to ensure it’s set correctly. Refer to your dryer’s manual for the proper settings. Incorrect purge settings can lead to wasted energy or diminished dryer performance.

Purge Exhaust Mufflers

These components reduce noise during depressurization and purging. Over time, mufflers can become clogged with desiccant dust, leading to higher back pressure on the regenerating desiccant tower. Inspect and replace mufflers every 6 to 12 months to maintain efficiency.

Latest Technologies

Advancements in dryer technology have made maintenance easier and more efficient. Modern regenerative desiccant dryers can now be equipped with automated systems that monitor filter status and valve performance in real-time. 

These systems can alert you to potential issues before they escalate, enabling predictive maintenance that helps avoid unexpected downtime. 

Additionally, smart sensors can optimize purge settings to reduce energy consumption, adjusting parameters based on operating conditions to maintain peak efficiency.

Future-Proofing Tips

To ensure your regenerative desiccant air dryer remains efficient and effective in the coming years, consider future-proofing your system with these upgrades.

Upgrade Control Systems

Replace outdated controls with modern, programmable logic controllers (PLCs) that offer better precision and adaptability to changing operational needs.

Integrate Remote Monitoring

Implement remote monitoring capabilities that allow you to track the performance of your dryer from anywhere. This is especially useful for facilities with multiple dryers or those in remote locations.

Adopt Energy-Efficient Components

Consider upgrading to energy-efficient components, such as low-power solenoid valves or variable frequency drives, to reduce operational costs.

Plan for Scalability

If you anticipate growth in your production demands, ensure that your dryer system can be easily expanded or upgraded to handle increased capacity.

Maximizing Desiccant Life for all Desiccant Dryers

With proper maintenance, activated alumina desiccant should last up to five years in heatless dryers and two to three years in heat-regenerated dryers. 

Deliquescent Desiccant also known as Absorbent desiccants - Dry-O-Lite, 10BF, SP (Special Purpose), and 4UF - actually absorb moisture and eventually dissolve. So, we recommend refilling the desiccant every 4 to 6 weeks. These tablets slowly dissolve at a rate relative to your inlet moisture content, temperature, pressure, and flow rate. So, we generally tell people they will need to top off every 4-6 weeks with an amount equal to about 1/3 of the overall desiccant bed. This would hold true for all 4 types of absorbent desiccants.

Regarding other considerations, regular maintenance of your desiccant air dryer isn't just good for your equipment—it’s also beneficial for the environment. By ensuring your dryer operates efficiently, you can reduce energy consumption, which lowers your carbon footprint. Properly maintained dryers also minimize waste, as they reduce the frequency of desiccant replacement and the need for emergency repairs that may involve the disposal of damaged components.

Stay Ahead with Preventive Maintenance

In 2024, the importance of preventive maintenance cannot be overstated. By following these guidelines, you’ll ensure your  desiccant air dryer delivers years of reliable service with minimal operational costs. Regular maintenance is the key to avoiding unexpected failures and maintaining the efficiency of your compressed air system.

For further assistance or to take advantage of our free desiccant testing service, don’t hesitate to contact us. Your dryer’s longevity and performance are our top priorities.