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With a water heater, the most common complaint is that it doesn’t heat water properly. Either it doesn’t heat water at all, it doesn’t heat it enough, or it heats it too much. Because a gas water heater operates much differently than an electric water heater, most repairs regarding improper heating depend on whether the appliance is gas or electric. For handling problems specific to one of these two types, see Gas Hot Water Heater Repairs and Electric Hot Water Heater Repairs.