Rinnai water heater age by serial number
Rinnai tankless water heaters made until late 2009 start the serial with the year and month, so their age is easy to read. Later units use a two-letter code that this Rinnai serial number lookup recognizes but does not decode yet, so check the Rinnai manufacture date printed on the label.
Where do I find the serial number?
Look on the side of the Rinnai cabinet for the rating label. On newer units, the manufacture date is usually printed beside the serial number.
How to read a Rinnai serial number
Older Rinnai serials are often printed as year, a dot, month, a dash, then the rest, so 04.03-102521 reads as March 2004. Some show the same digits without punctuation. From late 2009, Rinnai switched to a letter code where the first letter is the year and the second the month, and we will not guess at those until the letter tables are confirmed.
Year, month, then sequence (often printed YY.MM-sequence)
- Used
- Until late 2009
- Format
- Year, month, then sequence (often printed YY.MM-sequence)
- Example
- 04.03-102521
Example, read
Two letters then sequence
- Used
- Late 2009 to present
- Format
- Two letters then sequence
- Example
- CA-051306
Not decoded yet
From late 2009 Rinnai switched to a letter code (first letter year, second letter month). We have not yet verified the letter tables, so we will not guess. The manufacture date is usually printed next to the serial number on the label.
Where to find the serial number
Look on the side of the Rinnai cabinet for the rating label. On newer units, the manufacture date is usually printed beside the serial number.
Questions
How old is my Rinnai tankless water heater?
If the serial starts with digits, read the first two as the year and the next two as the month. 9704811080 reads as April 1997.
My Rinnai serial starts with two letters. Why can't you read it?
Those are the letter codes Rinnai has used since late 2009. We have not verified the tables yet, so we do not guess. The label usually shows the manufacture date next to the serial.
Do I type the dot and dash in a Rinnai serial?
You can. The decoder ignores dots, dashes and spaces, so 04.03-102521 and 0403102521 read the same.
Why are recent years not shown for the digit format?
Rinnai stopped using the year-first digit format in late 2009, so we only accept years up to 2010 for it.
Is the Rinnai date the installation date?
No, it is the manufacture date. Tankless units can be installed some time after they are made.
Can I look up a Rinnai model number here?
No. The Rinnai model number tells you which tankless model you have and its capacity. Dating it needs the serial number.