When Should I Replace My Water Heater?

Before we answer that common question, we should first discuss information about hot water in your home: how it works and measures your can take to reduce the cost of use. describe the image
Water heating is the second largest energy expense in your home. In a typical American home, according to the U.S. Department of Energy, water heating accounts for about 18% of total annual energy expenditures--a little more than for air conditioning, on a national-average basis, and twice as much as is used for refrigerators.

We all love the convenience of taking a nice hot shower. All you have to do is wake up some morning without hot water when you need to take a shower before work.

The way a water heater works is fairly simple. It's the big round metal tank usually located in the mechanical room in the basement near your furnace or the garage. They range in size from 20 to 80 gallons. It’s usually heated by the same heating source used in your furnace: gas or electricity.

Inside the tank of an electric water heater are two heating elements controlled by a thermostat outside of the tank. A gas water heater has a burner inside the bottom of the tank, similar to the burner on a gas stove, controlled by a knob outside the tank. A gas water heater will also have a chimney to allow the heated air from the burner to escape.

The tank actually has three layers: an inner tank where the water is stored, covered with insulating material such as polyurethane foam, and then an outer tank.

Inside your tank is the anode rod which is made of magnesium or aluminum and has a steel core; It helps keep corrosion at bay and give your water heater a longer life.

Outside the tank you’ll see a pipe that brings cold water into the tank, and another that takes hot water out of the tank. The cold pipe usually has a shutoff valve to manually shut off the flow of water into the tank if necessary. In normal operation the amount of water that flows into the tank is regulated by the tank’s pressure. There's pressure relief valve located on the top of the tank which regulates the pressure within safe limits. The drain valve near the bottom of the tank can be used to empty it when it needs to be drained for maintenance , if a gas burner needs to be replaced, or if the tank needs to be moved to a new location.

The process of heating the water is quite simple. When water at the bottom of the tank is heated by the burner, it rises to the top and the colder water sinks to the burner area. Cold water enters your water heater through the dip tube and goes to the bottom, where it’s heated. The hot water then rises to the top of your tank and is continuously heated while it waits to be requested, such as when you take a shower or turn on the dishwasher.
Everyone who's has multiple people who taking showers in the morning realize they don't want to be the last one when it 'runs out of hot water'. It just means the heating process couldn't keep up with the demand. So you have to let the water heater catch up.

Lets look at some interesting stats of the average hot water usage. Faucets and appliances can use a lot of hot water, which costs you money. Look for ways to heat your water more efficiently and use less.


Gallons per Use

Clothes washer




Automatic dishwasher


Kitchen faucet flow

2 per minute

Bathroom faucet flow

.05 per minute

Total daily average


Source: Federal Energy Management Program Energy Cost Calculator, March 2010

There are four ways to cut your water heating bills: use less hot water, turn down the thermostat on your water heater, insulate your water heater, or buy a new, more efficient model. The two easiest ways to reduce your energy use for hot water are to a) use less hot water, and b) reduce heat loss in your water heating and hot water distribution systems. We’ll take a look at each of these in turn.