Water Heater Question

[MJOLNIR]

I was just wondering after doing research on this. When water heaters in homes reach the end of their lives, do they just stop working, or do they always explode and create a flood?

If it's the latter, or if the latter is more common and thus the norm, how do you anticipate about when it will happen?

 

[clifford_cooley]

Water Heaters normally stop working due to heating elements in them going bad. I doubt the tank will ever explode, instead it would start leaking. Once the tank starts leaking it could get worse by the day.

There is what I would like to think a problem with our water company, putting too many chemicals in the water. This causes a build up in the tank covering the elements to a point the heater quits working.

 

[Nibiru2012]

It depends on where you live and how hard the watef is in your town. The harder the water the more lime buildup occurs.

Have you ever noticed when you boil water if any sediment occurs after it cools down? That's the lime settling out of solution.

Regardless of whether it's an electric or gas water heater, they need to be flushed via the drain valve at the bottom of the tank about once a year or else the lime scale builds up and take up space in the tank. With gas heaters the buildup will slow down the heat transfer from the burner to the water itself. Electric heaters don't have too much problem with that but the bottom element will eventually get covered up by the gradual buildup of lime and scale.

Modern water heaters no longer explode due to modern plumbing code requiring all installation to have a "T&P" relief valve installed with an outlet pipe to a floor drain or catch pan. T&P is short for Temperature & Pressure relief where if the heater's temperature or pressure build too high the valve activates and bleeds off the excess pressure and heated water.

Nearly most of the time, the internal glass lining of the tank will fail, the tank rusts and it will either leak at the side or bottom seams.

Some tanks will last 10 years or more with no issues, others less than five. Usually it's just a crap shoot to be honest about it, regardless of the water heater's price.

However, routinely draining the tank on a yearly or twice yearly basis is a good insurance against buildup and also helps to maintain the heater's energy efficiency. If it's a gas heater then it's always a good idea to visually check the burner flame while it's on to check and make sure the flame is as blue colored as possible.

 

[MJOLNIR]

What would you say is the average span? 10 years then?

Also when you say drain once a year, you mean just drain the water out right, not getting rid of build-up if any?

Also my water heater is 07-ish. Would you say it was built with the modern guidelines you highlighted?

 

[Nibiru2012]

Yeah, average span is about 7-12 years.

When you drain the tank, you leave the cold water line on, thereby the added pressure helps to flush the sediment out. Keep draining until the water runs clear.

Yes, it was built with the modern guidelines.

 

[Super Sarge]

I had one go bad it was 10 years old the bottom started to rot out and leaked, replacement cost plus installation was 700 dollars about 4 years ago

 

[Kalario]

I replaced mine with a tankless water heater, no more worries. Hot water on demand! Love it.

 

[yodap]

My wife works for an insurance company and they recommend replacement every 9-12 years. Of course if you buy the cheapest one you can find then it could be less time.

They usually start with a slow leak and get worse over time. Alarms are available that will go off as soon as they sense like a 1/16 of an inch of water.

 

[MJOLNIR]

I got at least two of those water alarms yodap, they are "Watchdog" brand.

 

[Kougar]

The heater in our current house was a little over 20 years old before it started showing signs of leakage, it was a premium model the original homeowner had bought. Talking with the crew that was switching it out, they mentioned the really cheap units last only about five years.

Nibiru is right in that maintenance is key to how long the unit will last... all the sediment in the bottom of a water heater can actually be heard... if you hear the boiling, bubbling, or the unit sounds like a peculating coffee pot then it's extremely past due for a cleaning. The sediment will block the heat from the burners, forcing it to heat for longer and hotter periods... this eventually will damage the metal / glass at the bottom of the tank and will quickly accelerate the decay until it begins leaking.

Maybe not even six months after we moved into our previous house (we stayed for one year) I luckily noticed the water heater had begun to leak... the heat from the burner would even evaporate the leak, but it only took about a week before it escalated into a small stream going across the garage floor. Once they begin leaking, they need to be replaced ASAP.

If you've ever seen the Mythbusters episode where they test the explosive power of a water heater, you will get an idea for just how much pressure (power) is contained in one of these things after they are heated. This is pretty much why they have temperature cutoffs and emergency vents [ame="[MEDIA=youtube]9bU-I2ZiML0[/MEDIA]"]‪Mythbusters Water Heater Explosion‬‏ - YouTube[/ame]

 

[jargonbust]

water heaters stop working when they are over heated
they never explode until the connection breaking element is failed due to some reason