Replacing your storage tank water heater with an on-demand or tankless unit can help you save energy, but before you make the switch, you need to understand key differences between these two water heating methods. First, consider how they work: Tank-style water heaters can keep 40–80 gallons of water hot and ready for use, so you can use the shower, dishwasher, kitchen sink and washing machine all at once. When the tank is depleted, though, it can take an hour […]