PVA support material is used in 3D printing for objects with complex geometries, holes, or overhangs.
PVA supports the shape of the model during 3D printing and then dissolves in water. However, due to its chemical properties, it is sensitive to humidity, so its quality during storage
decreases over time.
Let's look at some ways you can store and maintain PVA material for optimal results.
Ultimaker PVA filament formula is more sensitive to humidity than other PVA filaments, but there is still a correct way to care for it.
How to store PVA spools
Storing PVA under optimal conditions is key to high-quality 3D printing.
If not stored properly, PVA can absorb moisture from the surroundings (you'll notice it becomes soft, pliable, and even sticky) or become too dry (making it brittle),
both of which can lead to extrusion issues and print quality problems.
If moisture is the problem, you might see air bubbles in the PVA filament caused by moisture and hear popping sounds during printing. Print quality will decrease,
and poor PVA support layers can lead to print failure.
This can also lead to clogging of your BB print nozzle (read about how to fix a clogged print nozzle).

PVA prints correctly. If PVA is damaged, discoloration and poor layer adhesion will occur.
One of the best ways to avoid any issues is to store PVA in a sealed container when not in use. If you have Ultimaker PVA, we recommend reusing
the resealable bag and desiccant from the original packaging, which should keep it in good condition when you want to use it.
Some third-party manufacturers offer other solutions, such as professional filament storage boxes, or you can use other types of airtight containers.
The optimal storage temperature for PVA is between 0°C and 30°C, with a recommended relative humidity of less than 50% in the storage area. It is also advised to avoid direct sunlight.
What if your PVA loses its good quality?
If your PVA does absorb moisture, it can still be dried again.

Drying PVA filament on an Ultimaker 3D printer bed
The easiest way to dry filament is to use the heated bed of an Ultimaker 3D printer. Place the spool inside a cardboard box (such as an Ultimaker filament box) and place it
on the bed, heating it to 55°C, and wait a few hours while the filament dries.
To do this using the Ultimaker 3 menu, go to System > Print bed and manually change the print bed temperature.
Original source:https://ultimaker.com/en/blog/52493-3d-printing-tips-how-to-store-pva-material