Thank you for the question. The ideal temperature for a hot water wash is 105° - 125°F, though this is dependent on the water heater settings in your home. It's not unusual for cold water remaining in the pipes to cause the temperature of the water filling the drum to be colder than that. To ensure the water supplied through the hot water pipe is indeed hot, some people choose to run hot water through a nearby faucet just prior to the start of a hot water cycle.
The WA5471 does have a Sanitize option available which uses the internal heater to boost the temperature of the water to about 150°F, though this may be too hot for some fabrics. I would suggest checking your hot water heater setting to ensure it is set between 110-120°F. To determine if your washer is filling correctly, try turning off the cold water supply valve. If the water temperature is hotter when the washer has no access to the cold water supply, service may be needed. Please submit your contact information to our support team through the link below, or call 800-SAMSUNG to speak with an agent who will be happy to assist you.
Online support form: http://www.samsung.com/us/support/o...
- Ms. Samsung