GRU recommends a setting of 120 degrees for domestic hot water heaters. If dishwashers have pre-heaters or boosters, you may be able to reduce tank settings from 140-150 degrees to 120 degrees. Hot water to bathrooms may be disconnected or turned off at the lavatories, since most customers do not require available hot water for hand washing. Using minimum water heater settings reduces the energy demand of the tank and excessive heat given off by the water heater. Following these tips will help you save water and money: