How to Verify the Installation Date of a Water Heater

Carrie Perles

When a water heater breaks down, it can cause a lot of damage. Therefore, it is important to know when you should start thinking about replacing your water heater. Although the amount of time that a water heater is expected to last varies in different locations and situations, many water heaters can be expected to break down in 10 to 15 years. Knowing the installation date of your water heater can help you figure out the correct time to replace it.

  1. Check the manufacturer of your water heater. Although there are hundreds of brands of water heaters, there are six main manufacturers that produce the vast majority of those brands: American Water Heater Company, A.O. Smith Corporation, Bradford-White Corporation, Lochinvar Corporation, Rheem Corporation and State Industries.

  2. Locate the code on the side of the water heater.

  3. If the manufacturer is American Water Heater, look at the first four digits. The first two represent the year, and the second two represent the week. For example, if the first four digits are 0403, the heater was installed in the third week of the year 2004.

  4. If the manufacturer is A.O. Smith, look at the second, third and fourth character. The second character should be a letter between A and M (excluding I), which represents the month of the year. The third and fourth characters represent the year. For example, if these three digits are A06, the heater was installed in January of 2006. If the manufacturer is State Industries, look at the first three characters in this manner.

  5. If the manufacturer is Bradford-White or Lochinvar, the process is a bit more complicated. Look at the first two characters---both letters. The first letter represents the year of a 20-year cycle that the heater was installed. The first cycle began in 1964, symbolized by the letter A. Each letter symbolizes the next year of the cycle, with I, O, Q, R, U, and V left out (to leave only twenty letters). The second letter represents the month. For example, if the first two characters are BB, the unit could have been installed in February of 1965, 1985 or 2005.

  6. If the manufacturer is Rheem, the first four numbers represent the month and the year. For example, if the first four numbers are 0298, the heater was installed in February of 1998.