Bosch Age Lookup

Bosch Age Lookup — How to Decode Your Serial Number

How to decode a Bosch serial number to find the manufacture date — Greentherm, Greenstar, and Tronic decoding.

Updated May 2026 · Bosch Water Heaters

Bosch serial numbers encode the manufacture date — though the format differs slightly between Greentherm (gas tankless), Greenstar (combi), and Tronic (POU and electric tankless).

Where to find the serial

  • Data plate on the side of the unit
  • Home Comfort app for paired Greentherm 9999 SE units
  • Installation paperwork if available

Greentherm and Greenstar — alphanumeric format

Greentherm and Greenstar serials typically start with a letter prefix followed by date code. Format:

  • First letter = factory location identifier
  • Next 4 digits = year and week (e.g., 2245 = week 45 of 2022)
  • Remaining digits = factory sequence

Example: G224500123 = Factory G, week 45 of 2022, unit #123.

Tronic POU and Tronic Heat — numeric format

Tronic serials are typically 10-12 digits. Format:

  • First 2 digits = year (22 = 2022)
  • Next 2 digits = month (01-12)
  • Remaining digits = factory sequence

If format is unclear

Call 1-866-642-3198 with the serial number. Bosch support can confirm the manufacture date in under 5 minutes.

Cross-check against the model

Model lineProduction years
Greentherm 9999 SE2024-present
Greentherm 9900 SE2020-present
Greentherm 9000 / 9000 SE2014-present
Greentherm 53002018-present
Greenstar 100 / 131 / 1512014-present
Tronic 6000 C2018-present
Tronic 3000 T2010-present
Tronic Heat 30002015-present

Warranty implications

Warranty runs from install date if registered; from manufacture date if not. See warranty hub.

Bottom line

Decode the year from the serial; cross-check against the model's production years. Call Bosch if format is unclear.