The amount of time it takes to get hot water from a new water heater depends on the size and type of hot water heater. A properly and professionally installed gas hot water heater will provide hot water most quickly. An average 40-gallon heater will only take about 30 to 40 minutes to provide heat water, while you can expect hot water from a larger tank (80-gallons) in approximately 60 to 70 minutes. Electric hot water tanks, on the other hand, will take a little longer. For an average 40-gallon electric heater it will take about 60 to 80 minutes and for an 80-gallon tank about 2 hours.
