Paloma water heaters carry the build date inside the serial number. We know 3 serial formats for this brand; the decoder tries each one and shows every reading that fits.
Skip any letters at the start. The first two digits are the month and the next two are the year. If the first two digits are 13 or higher they are the week instead.
RMLN0109J000472 reads as January 2009.
Two sources agree InspectAPedia, Building Intelligence Center
On tankless units with a period in the serial, one source reads the two digits before the period as the year and the two after as the month.
05.05-000021 reads as May 2005.
One source Building Intelligence Center
Another source reads the two digits before the period as the month and the two after as the year.
05.05-000021 reads as May 2005.
One source InspectAPedia
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 · Navien · Noritz · Takagi · Bosch (tankless water heater) · Lochinvar · GSW / John Wood · 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.
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Galvanized, polybutylene, cast iron and the sewer line: what fails, what it costs, what insurance won't cover and how to decide.
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