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Water Heater Age | Tankless Pros Az | Phoenix, Az

Water Heater Age

FAQs About Water Heater Age

Before you determine the age of your water heater, review some of the frequently asked questions when it comes to water heaters and the age of your water heater.


How old is my water heater?

When owning a water heater, it is important to know your water heater's age in order to decide whether it is time to service or replace your water heater. If you have owned a water heater for a long time or just moved into a new home with a water heater you are not familiar with, then it would be a good idea to determine the age of your water heater.


How long do water heaters last?

A water heater can last anywhere between 8-12 years in the Phoenix area. Once you calculate the age of your water heater, you will then need to determine if the age of your water heater is past due for maintenance or replacement.

We will list the most popular brands in this water heater age guide so that you can determine your water heater’s age.


When should I replace my water heater?

Your water heater should last you many years and you should have a good idea of how much longer your water heater will last by reading the serial number to decipher the manufacture date of your water heater. 

Keep in mind these 5 things when deciding the right time to replace your water heater:


  1. Water Heater Age: The general lifespan of a water heater is 8-12 years. This is why it is important to determine the age of your water heater and it is recommended to replace your water heater before its 12th birthday.

  2. History: Have you had trouble with your water or even repair work done. These are important factors when considering a replacement or upgrade even sooner.

  3. Less Hot Water: If you are experiencing a decrease in hot water throughout your home, then it may be time to replace your water heater due to your water heater’s age.

  4. Higher Heating Bills: As a water heater grows older, it takes more energy to produce hot water. An increase in heating bills may be a good indication that your water heater is getting old and it’s time for a replacement.

  5. Corrosion: If your water heater is beginning to corrode, then this is means your water heater is significantly old and it is time for a replacement.


Determining The Age Of A Water Heater

The first two characters of the serial number represent the year and month of manufacture. The remainder of the serial is a sequential production number, seven digits in length before December 2007 (DM), and eight digits in length after.

Serial number as located on the water heater: NB37365153

Date of manufacture using the chart below: February - 2016

For example:
Production Year

A = 1984 or 2004

B = 1985 or 2005

C = 1986 or 2006

D = 1987 or 2007

E = 1988 or 2008

F = 1989 or 2009

G = 1990 or 2010

H = 1991 or 2011

J = 1992 or 2012

K = 1993 or 2013

L = 1994 or 2014

M = 1995 or 2015

N = 1996 or 2016

P = 1997 or 2017

S = 1998 or 2018

T = 1999 or 2019

W = 2000 or 2020

X = 2001 or 2021

Y = 2002 or 2022

Z = 2003 or 2023

For example:
Production Month

A = January

B = February

C= March

D = April

E = May

F = June


G = July

H = August

J = September

K = October

L = November

M = December

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