People who are considering spending hundreds of dollars on a storage tank heater and then a few more for a tank-less or a solar model first need to consider if their existing heater can be fixed.
In the case of hot water storage tanks if it's corroded you might as well replace it but if it's a leaky drain or a bad pressure relief value or even a bad heating element all of these can be fixed for around $50.
If your existing storage tanks cannot be fixed then why not opt for a tankless system. Companies have some of the best solar and tankless systems at https://www.kliptank.com/products/covered-tanks/ which can put a significant dent in your gas or electricity bills. That being said these systems are more expensive than conventional water heating systems.
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The right capacity tank
The first thing you ought to determine is the capacity of the tanks you want to purchase. Most heating tanks are sold based on how many gallons of water they can store.
A good rule of thumb for knowing the right capacity is four people can use up to around 85 gallons a day or three showers, laundry, and a running dish washer. The average family can easily get through with an 80-gallon tank; a family of six to eight may want to opt for a 100-gallon tank.
Gas or electric hot water storage tanks
This valve opens when either one of the water inlets exceeds its present level. There is also a handy drain valve close to the bottom and a small control unit on the outside where users can set the temperature on gas models.