Hello: A tankless heater, if it’s placed where your current heater is, will only make it take longer to get hot water. When you turn on the tap now, hot water starts flowing immediately from the tank. A tankless unit takes around 7-15 seconds before hot water starts coming from the unit. So, one choice is to put a demand controlled pump in http://www.gothotwater.com and leave the heater where it is. Hope that helps.