Rheem water heater age by serial number
Rheem water heaters print the month and year of manufacture as four digits near the start of the serial, sometimes after a few letters. Type the serial from the label into this Rheem water heater serial number lookup to find the Rheem manufacture date.
Where do I find the serial number?
Rheem tank water heaters have the rating label on the side of the tank, usually just above the gas control or, on electric models, above the upper element cover. Tankless Rheem units show it on the side or bottom of the cabinet.
How to read a Rheem serial number
On most Rheem water heaters, the first four digits of the serial are the month, then the year. A letter prefix such as RHNG may come before them, so RHNG 0804P000036 reads as August 2004. Newer sixteen-character serials use a different layout that we recognize but do not decode yet.
Month, year, plant letter, sequence (optional letter prefix)
- Used
- 1970s to present
- Format
- Month, year, plant letter, sequence (optional letter prefix)
- Example
- RHNG 0804P000036
Example, read
Some serials start with letters such as R, RU, RN, RNG or RHNG. The date is the first four digits after them.
Tankless units may print the serial as month and year, a dot, then the rest. You can type it with the dot.
Sixteen-character serial
- Used
- Recent
- Format
- Sixteen-character serial
- Example
- D1114A441408265A
Not decoded yet
This longer Rheem format is recognised, but we have not been able to confirm how it encodes the date. Check the manufacture date printed on the rating plate.
Where to find the serial number
Rheem tank water heaters have the rating label on the side of the tank, usually just above the gas control or, on electric models, above the upper element cover. Tankless Rheem units show it on the side or bottom of the cabinet.
Brands with the same format
Ruud uses the same serial format as Rheem.
Questions
How old is my Rheem water heater?
Skip any letters at the start and read the first four digits as month and year. 1209D01234 reads as December 2009.
What if my Rheem serial is sixteen characters long?
That newer format, such as D1114A441408265A, is one we recognize but cannot yet decode reliably. Check the label for a printed manufacture date instead.
My tankless Rheem shows the serial with a dot. How do I type it?
Type it as printed, dot included. The decoder ignores dots, dashes and spaces, so 08.04-12345 reads as August 2004.
Is a Rheem water heater serial read like a Rheem furnace serial?
No. Rheem heating and cooling equipment puts the week and year after a plant letter. Water heaters use month and year, so pick the right type.
Does Ruud use the same serial format for water heaters?
Yes. Ruud water heaters use the same serial format as Rheem water heaters.
Can I look up a Rheem model number here?
No. A Rheem water heater model number describes the fuel type, tank capacity and series. Only the serial gives the manufacture date.