Find the manufacture year of any Navien tankless water heater or combi-boiler from the serial number.
Tankless Water HeaterCombi-BoilerCondensing Boiler
Enter Serial Number
How to decode the serial number
Navien is a leading manufacturer of condensing tankless water heaters and combi-boilers. Their serial numbers encode the manufacture year and month.
2010 to Present
Characters 3–4 = year, characters 5–6 = month.
AU1701123456
Position
Meaning
Example
1–2
Plant/model code — Plant identifier
AU
3–4
Year — 2017
17
5–6
Month — January
01
7+
Sequence — Ignore
123456
Where to find the serial number
The data plate on a Navien unit is on the front panel behind the cover or inside the front door.
Many Navien units display error codes and diagnostics on an LED panel — the installation manual is usually attached inside.
Decoded examples
AU1701123456
→ January 2017
AU = plant, 17 = 2017, 01 = January
KD2308456789
→ August 2023
KD = plant, 23 = 2023, 08 = August
Life expectancy
Expected lifespan: 15–20 years for Navien condensing equipment. Navien is a premium brand with strong warranties.
Common questions
Navien condensing tankless water heaters are designed for 15–20 year lifespans. The heat exchanger carries a 15-year warranty on most residential models. Annual descaling in hard water areas is important for longevity.
Characters 3–4 of the serial number are the 2-digit year, and characters 5–6 are the 2-digit month. Example: AU2308 = August 2023.