Avoid at all costs: Moist hot-melt adhesives
Generally speaking, hotmelt adhesives should be stored dry at room temperature.
If, for example, granules that have become moist due to unfavourable storage conditions are melted in a hot tank, hot water vapour is produced by the escaping moisture.
Up to 25l of vapour can develop from 20g of water. The hot melt adhesive foams and rises in the tank.
Granules that have become moist must be dried before use. To do this, the granulate should be spread out in a warm and dry area so that it can dry. After that, it is safe to use again.
The short video shows the melting behaviour of a slightly moist adhesive.