Primer ยท Hot Water
How Long Water Heaters Last
Water heaters rarely fail on a convenient day. Knowing roughly how old yours is, and what wears it out, lets you replace it on your schedule instead of the tank's.
- Plain steps you can do yourself, safely
- Clear signs for when to stop and call
- Written for Newmarket houses and water
- A plumber on the phone if it goes sideways
What goes wrong in the pipes
A standard tank water heater, gas or electric, commonly lasts somewhere around eight to twelve years. Some go longer, some fail early. Tankless units often last longer, sometimes twenty years with good maintenance. The range is wide because the things that wear tanks out vary from home to home: water hardness, how hard the tank works, how well it has been maintained, and simple luck in manufacturing.
When a tank fails, it often starts with a slow leak, but sometimes the bottom gives way and dumps its contents into the basement. Planning ahead avoids that flood and the scramble that follows. It also gives you time to compare models and prices calmly, rather than accepting whatever is on the truck at eleven at night.
Have these on hand
- Bucket and garden hose
- Flat screwdriver
- Flashlight
- Phone camera for the rating plate
Hands-on steps
- Find the age. Look at the rating plate on the tank. The manufacture date is usually printed there or encoded in the serial number. Manufacturers often publish how to read their serial codes.
- Check who owns it. If there is a rental company sticker on the tank, you may be renting. That changes who handles a replacement.
- Look at the base. Rust, moisture or mineral streaks around the bottom of the tank are warning signs.
- Listen. Crackles and rumbles during a burn point to scale and silt settled on the tank floor.
- Test the relief valve. The temperature and pressure relief valve should release water when lifted briefly. If it drips constantly afterward or will not open, it needs attention.
- Flush annually. Draining some water from the bottom removes sediment and can extend tank life.
Mistakes that turn a small repair big
- Waiting for a flood. A tank past its expected life with signs of corrosion is worth replacing on your own schedule.
- Cranking the temperature. Running the tank very hot speeds up scale and wear.
- Ignoring a dripping relief valve. It is a safety device; a drip may point to excess pressure or a failing valve.
- Choosing by footprint alone. Your household may have changed since the last tank went in. Size the new one to how you live now.
When to put the tools down and call
Call when the tank leaks, when hot water turns rusty, when it runs out much faster than it used to, or when the burner or elements keep failing. Some issues, like a faulty thermostat or element, are fixable with water heater repair. Others mean it is time to replace.
If you are replacing anyway, think about whether a different type suits you better. Our guide comparing tank and tankless water heaters lays out the trade-offs, and our tankless installation page explains what that switch involves.
Asked on site
How do I know if my water heater is about to fail?
Common signs include leaks at the base, rusty hot water, rumbling noises and a shrinking supply of hot water. Age alone is also a strong indicator.
Is it worth repairing an old water heater?
For a newer tank with a simple fault, yes. For an older tank showing corrosion or leaks, replacement usually makes more sense.