First make sure it is set to 120 degrees Fahrenheit. Hot water above 120 can be considered hazardous. The higher the degree, the more your hot water heater has to work to keep that high temperature, coming on more often and making you have a higher energy bill.
Setting a timer on the hot water heater to come on and off will certainly help out. Contact a plumber to install the timer, or do it yourself. If a timer is not what you want, you could schedule a time of day that you and your family will need showers, cook and wash dishes, etc.
If your family is out of the house for the day, you could to be at work, the kids at school, etc, then why have the water heater going all day with no one home. Turn it on when you get home and allow 20 minutes or less, depending on what kind of water heater you have, to heat up.Going on vacation? Turn it off and save money while your gone.
Hold in the heat by adding an insulator also known as wraps, jackets or blanket. You can find these at your local hardware store.
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