Van Air offers two types of desiccant cartridges. Model ID15/SW uses a disposable silica gel cartridge. The beads are impregnated with a moisture indicator. A sight window on the body of the dryer is present to view the condition of the silica gel, which turns from blue to pink when saturated with moisture, signaling that it's time to replace the cartridge.
Model ID15/IND uses a disposable molecular sieve cartridge and has a moisture indicator on top of the dryer housing that indicates the condition of the material in the cartridge.
Replacing the mini-dryer cartridge is a quick procedure. No tools are needed and there is no handling of desiccant involved. Changing the cartridge only takes minutes. No regular maintenance is required. Van Air mini-dryers can be installed inside or outside in ambient temperatures up to 40°C. Only inlet and outlet connections are needed. Mini-dryers perform effectively under cyclic or sporadic flow conditions. Pressure drop across the dryer is negligible.
The ID35 uses a sacrificial bed of loose silica gel desiccant that can be drained through a plug at the bottom of the vessel. New silica gel is added at the top.