ANSWER: The ProHeat Series features a heating element which increases the temperature of the water and solution up to an additional 25 degrees than the temperature of water placed in the tanks, before dispensing onto the floor. The maximum temperature is approximately 180 degrees Fahrenheit.The heating element will not maintain the temperature of the water in the tank and does not apply when using the upholstery attachments.For more information, please contact a BISSELL Consumer Services Representative by calling 1800 811 183 or australiacustomerservice@bissell.com.