Ruud water heater age by serial number
A Ruud water heater serial usually opens with a short letter prefix, then the month and year it was made. Enter the full serial in this Ruud water heater serial number lookup and it will skip the letters and give the Ruud manufacture date.
Where do I find the serial number?
Look on the side of the Ruud tank for the rating label, generally at about knee height near the controls. On a tankless Ruud, check the sides and underside of the cabinet.
How to read a Ruud serial number
Ruud water heater serials often begin with letters such as RU, then four digits for the month and year, then the rest of the serial. Tankless units may show the date as month, a dot, then year.
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
Look on the side of the Ruud tank for the rating label, generally at about knee height near the controls. On a tankless Ruud, check the sides and underside of the cabinet.
Brands with the same format
Rheem uses the same serial format as Ruud.
Questions
How old is my Ruud water heater?
Ignore the letters at the start and read the next four digits as month and year. RU 0904B21710 reads as September 2004.
My Ruud serial is a long mix of letters and digits. Why won't it decode?
Some recent Ruud serials use a sixteen-character format that we recognize but have not confirmed. Look for a printed manufacture date on the label instead.
Do the letters at the start of a Ruud serial matter for the date?
No. They are a prefix. The date is the first four digits after them.
Does Ruud use the same serial format as Rheem?
For water heaters, yes. Ruud and Rheem water heater serials are read the same way.
When was my Ruud water heater installed?
The serial only gives the manufacture date. Installation is usually a little later, and a permit record or a dated receipt will show the exact day.
Can I look up a Ruud model number here?
No. The Ruud water heater model number covers things like fuel and tank size. We decode the serial number, which holds the date.