To ensure positive operation of systems, storage cylinders must be purged of moisture periodically. This is accomplished by slightly cracking the moisture drain fitting, located on the cylinder manifold. Some aircraft have a pneumatic system that will maintain the required pressure in these bottles in flight. However, most of these pneumatic systems require servicing on the ground with an external source of high-pressure air or nitrogen prior to each flight. Air storage bottles are serviced in the same manner as accumulators.
Most air bottles have an air filler valve and a pressure gauge.
These systems generally require higher servicing pressure than accumulators. Since gases expand with heat and contract when cooled, air storage bottles are usually filled to a given pressure at ambient temperature. Pneumatic storage cylinder inflation chart. Pressure should be added to air storage bottles slowly in order not to build up heat from rapid transfer. You should take care to ensure that air storage bottles are not overinflated.