Hugh Cairns: Your aging hot water tank

The reliable life expectancy of hot water heaters is usually related to in-service age. Photo: Contributed – (Hugh Cairns)

Hugh Cairns: Your aging hot water tank

How old is the hot water tank? Does it need replacing? These are some of the hot water tank questions that I am routinely asked while conducting a home inspection. They are actually simple questions with many different answers. The bottom line is that we should make calculated decisions to replace our deteriorating hot water tanks well before they can cause pressurized water damage to a home.

Of course, the most common indicator that the hot water tank needs to be replaced is that it is leaking. When it comes to hot water tank leaks, it’s a safe bet to say that the leak is non-repairable and that the unit needs immediate replacement. Be careful though, there have been rare times when plumbers have gone out to replace a hot water tank and discovered that the leak was unrelated to failure of the tank itself and a routine fix was conducted.

How often should you replace hot water heater?

Hot water heaters can last decades without a problem, however for insurance purposes, the widely accepted reliable service life of tanked water heaters ranges from 8 to 12 years (or the published warrantied period), so your tank may appear to be operating just fine and probably is, but your insurance underwriter may require a new tank to reduce risk. Insurance underwriters tend to categorize aging water heaters differently than newer ones so ultimately it is their opinion that is the one that is recognized over anyone else’s. If you are buying a home with an older tank, you may have to replace it to satisfy your underwriter.

How old is your hot water heater?


The reliable life expectancy of hot water heaters is usually related to in-service age. There are few consumer products that a clearly marked with a manufactured date and hot water heaters are one of them. It is safe to say that hot water heaters are installed in short order after their manufactured date. That is why most home inspection professionals determine the manufactured date of the tank as a basis to estimate in-service age, and in turn, its remaining reliable service life.

In order to find out when your water heater was manufactured look for its serial number. The serial number has specific digits that represent the year of manufacture. Hot water tank age chart.