Navien water heaters carry the build date inside the serial number. We know 2 serial formats for this brand; the decoder tries each one and shows every reading that fits.
Skip the first five characters (a model code). The next two digits are the year, then one character for the month (1 to 9, then X for October, Y November, Z December), then two digits for the day.
7414C14X1771143 reads as October 17, 2014.
Two sources agree Building Intelligence Center, Fast Water Heater Co., Tankless Help, McGarry and Madsen Home Inspection
The eight digits in the middle are the full year, month and day.
9262-20081208-1027 reads as December 8, 2008.
Two sources agree Building Intelligence Center, Fast Water Heater Co., Tankless Help
A gas tankless water heater usually lasts 15 to 20 years, and sometimes longer, because there is no tank to rust through. Scale buildup in the heat exchanger is what shortens its life.
How long does a tankless water heater last? · Should I replace my water heater? · DC Dept. of Energy & Environment, U.S. DOE Building America
A.O. Smith · American Water Heater · U.S. Craftmaster · Bradford White · State · Reliance · Kenmore · Whirlpool · Rheem · Ruud · Richmond · GE · Marathon · Rinnai · Noritz · Takagi · Bosch (tankless water heater) · Lochinvar · GSW / John Wood · Paloma · HTP / Westinghouse / American Standard (water heaters) · Giant · EcoSmart / Eemax · Stiebel Eltron
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The age you just looked up is the kind of fact that gets lost. A written record of serial numbers, install dates, repairs and who did the work saves the next owner, inspector or insurer from guessing.
A lifetime logbook for the house, organized by system, with room for serial numbers, install dates, repairs and contractors. It stays with the house for the next owner.
Galvanized, polybutylene, cast iron and the sewer line: what fails, what it costs, what insurance won't cover and how to decide.
A buyer's guide to older homes: wiring, pipes, lead, asbestos, insurance refusals and what the repairs actually cost.
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