Our advice is always to dye at the maximum permissible temperature according to the washing instructions of the garment. Remember, however, that the higher the temperature, the better the colour rendition on the fabric will be. In the washing instructions for garments, a lower maximum permissible temperature is often indicated as a precaution. In the case of specific fibres, under certain conditions, a higher temperature than indicated may be reached. Most wool compositions, for example, dye very well at a temperature of 90/100°C. Felting occurs mainly due to sudden changes in temperature or repeated rubbing. If heated and cooled gradually, wool can withstand high temperatures. There is a lot of information available on the Internet on the dyeing of different materials. At your own risk, experimenting with water temperature can lead to excellent results.