An anode rod is built into the tank to attract corrosive elements from water. This protects its interior lining. The rod becomes useless after a long time of use with the tank water heater (about ten year). The rod is then destroyed by the corrosive particles that settle on the tank's interior, including its bottom.
As mentioned above, several things can cause a home's hot water supply to run out faster than it should. The three most common culprits are sediment build up, a faulty heating element and a broken dip tube.
While the typical water heater has a lifespan of about 10 years, careful consideration of the factors that pertain to its lifespan can provide the InterNACHI home inspector and the homeowner with information about the potential costs that would be incurred by replacing the water heater.
Sediment buildup shortens the life of your water heater and adds to your energy bill by reducing its efficiency. Draining two or three gallons of water is usually enough to flush out sediments, but always let the water flow until you no longer see particles in the bucket.
Old water heaters are much less energy efficient, both because they are aging and because standards were lower back then, which could mean more money you're paying each month in energy costs compared to a newer heater. It's generally accepted that most water heaters last an average of about 13 years.
Delivering Rusty or Cloudy Water
Rust deposits or a metallic odor coming out with hot water can signal either rusty pipes or rust inside the water heater. If corrosion is eating away the metal from the inside, leaks are inevitable. Murky water from the tap can also be signs that the water heater will fail soon.
3. Water heater is losing efficiency. Another downside about old water heaters is that they lose efficiency over time. That's why a big sign for when to replace your water heater is a steady rise in water-heating costs year after year.
Water Heater Lifespan
If your tank water heater is more than 10 years old, it may be time to consider replacing it. With proper maintenance, a tank water heater tank should last six to 12 years. A tankless water heater can last for more than 20 years.
A tankless water heater can last up to 20 years, sometimes even longer. Also called “on-demand” water heaters, these appliances do not work continuously to maintain a supply of hot water—and, as a result, they last longer than their tank-style counterparts.
A professional can sometimes repair these issues, but if your water heater is older, you'll need replacement. For example, a 20-year-old water heater is nearing the end of its service life and will need to be replaced even if repairs are possible.
This happens over time as your water heater ages. If you haven't maintained your water heater with annual system flushes, this could be the problem. Sediment is formed from loose minerals that are found naturally in water. When they settle at the bottom of the tank, it causes your tank to run out of hot water quickly.
Over time, minerals in the water can build up at the bottom of the water heater tank where the burner is located. This causes a gradual reduction in heating efficiency that will make the water heater work harder and eventually resulting in less hot water.
You're overusing hot water. The water heater tank size is too small for your household. Your hot water heater is tankless. Sediment or minerals have built up in your water heating system.
Short of a plumbing emergency, this is a big reason to replace your water heater, as not only can it lead to the issue worsening over time, but can cause your energy bill to skyrocket to keep up with the overwhelming needs to keep your water hot.
Here's the catch: Modern water heaters are well-insulated meaning there is very little heat loss. Although electrical rates vary, the experts say turning off the water heater at night will likely save about two dollars a month.
It's generally a good idea to drain your water heater at least once a year, according to both BobVila.com and The Family Handyman. If you live in an area with hard water, though, Angie's List says you may need to drain it more frequently.
Flush your water heater every six months or so. If you have harder water, or water that contains more minerals, you may want to flush it more often. If you leave town, change your water heater to its vacation setting.
6. Water Heaters. Water heaters turn over in early fall. Time your purchase for September or October, if possible, or wait until the new year (January) for postholiday clearance sales.
Rheem hot water systems have a typical life span of between 5 and 15 years depending on water conditions and how well the system has been serviced. You can add years to the life to a Rheem hot water system if you have it serviced every 5 years.
The two main issues are a leaking TPR, or there is poor water flow through the pipe when you test the valve. Buildup of rust, mineral deposits, and corrosion can cause a TPR valve to freeze and fail to function properly.
With nothing more than a once-per-year flushing maintenance service, a tankless water heater can easily last 20 to 30 years, and some will even last quite a bit longer.