Master Plumber Water Heater Serial Number Lookup & Age
Find supported Master Plumber water-heater date codes, older brand-label context and the separate model number needed for manuals. Confirm the manufacturer and serial system before decoding.
Water heaters with confirmed manufacturer and numbering family; unrelated devices using the same name are outside these date-code rules.
Explore a sourced example:
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Master Plumber serial numbers by device type
Match the product, manufacturer and documented serial layout before interpreting a date. The model is a separate label field; a date code alone does not identify capacity, installation date or warranty entitlement.
Master Plumber water heaters — American-built family
For Master Plumber water-heater labels: the historical chart associates this label with American water heaters. A confirmed American tank may encode the two-digit year followed by the production week. This format is separate from appliance codes and does not encode the complete model. Confirm the builder and matching serial layout before choosing a system.
For Master Plumber water-heater labels: a confirmed State-family tank can use year/week or documented older letter-month/year systems. Historical month alphabets differ: one table includes I and a later table skips it. In the chart’s year/week layout, 0904 means year 2009, week 04; it does not mean April. Use the labelled build date to resolve context.
Manufacture date is different from installation, purchase and warranty start dates.
Enter the separate model number from the rating plate to search for the correct manual. These date positions do not establish a full model, capacity, fuel type or warranty entitlement.
The historical inspection chart is secondary evidence of listed brand relationships, not proof of the manufacturer, product family or date system on a particular unit. Confirm the actual label and select the matching system explicitly.
A missing match does not establish age, authenticity or condition. Unsupported eras and device types require the manufacturer or model-specific documentation.
This name appears under more than one historical manufacturer group. Review every applicable family; the brand name alone does not select one.
Options labelled historical supplied-chart systems rely on secondary evidence and preserve an unresolved century unless you provide separate era context.
Research reviewed October 16, 2026. This independent tool applies published rules and retains unresolved years and model candidates.
Confirmed water-heater family: Water heaters: year and production week
Water heaters only after confirmation of this manufacturer, product family, date-code layout and documented era.
YYWW: first two digits year; next two production week. The 2024 manufacturer guide permits week 53. No model, capacity, fuel or installation date is encoded by these four digits. 2008 is a conservative supported-range limit, not an asserted universal changeover. The October 2016 SAP change uses a 13-character printed date-plus-serial. A bare nine-digit barcode/SAP serial has NO date code and is deliberately not decoded. The supplied historical inspection chart lists additional names, but that relationship does not prove the manufacturer of every product bearing the same brand. This option requires independent confirmation from the unit label or model-specific documentation.
Confirm that this is a water heater and that its rating plate or model-specific manufacturer documentation uses this exact numbering family. A historical brand list or a matching serial shape alone is insufficient.
Historical American-family supplied-chart YYWW system
Historical 2010 TIJ chart’s American/Craftmaster/Mor-Flo/private-label list only, with explicit water-heater/manufacturer confirmation.
This is secondary-chart evidence, not a currently manufacturer-verified universal rule. The supplied anonymized 9746******means year ending 97/week 46 in its 1997 worked context.2010 is a conservative reviewed-publication horizon, not a claim the system endedthen. The chart’s American acquisition year 2001 is wrong; ownership history must not establish a serial-era cutoff.
Select only after confirming the water heater or boiler family and numbering system described here. Brand ownership alone does not establish this system.
Confirmed water-heater family: Water heaters: letter month and year, 2004-2007
Water heaters only after confirmation of this manufacturer, product family, date-code layout and documented era.
Manufacturer/CPSC notices document the A-L/M month series with I omitted: L 07 is November 2007; M 07 December 2007. This rule is intentionally limited to the observed 2004-2007 family. The supplied historical inspection chart lists additional names, but that relationship does not prove the manufacturer of every product bearing the same brand. This option requires independent confirmation from the unit label or model-specific documentation.
Confirm that this is a water heater and that its rating plate or model-specific manufacturer documentation uses this exact numbering family. A historical brand list or a matching serial shape alone is insufficient.
Confirmed water-heater family: Water heaters: plant and month letters, early 2004
Water heaters only after confirmation of this manufacturer, product family, date-code layout and documented era.
The January-June 2004 recall serial-prefix table includes a leading plant character before the month. Do not strip an arbitrary leading letter from every later serial. The supplied historical inspection chart lists additional names, but that relationship does not prove the manufacturer of every product bearing the same brand. This option requires independent confirmation from the unit label or model-specific documentation.
Confirm that this is a water heater and that its rating plate or model-specific manufacturer documentation uses this exact numbering family. A historical brand list or a matching serial shape alone is insufficient.
Confirmed water-heater family: State historical month letters, 1991-2002
Water heaters only after confirmation of this manufacturer, product family, date-code layout and documented era.
Archived State manufacturer FAQ lists 1991-2002 and A-L with I included, I=September. This differs from later skip-I formats; do not combine the month tables. The supplied historical inspection chart lists additional names, but that relationship does not prove the manufacturer of every product bearing the same brand. This option requires independent confirmation from the unit label or model-specific documentation.
Confirm that this is a water heater and that its rating plate or model-specific manufacturer documentation uses this exact numbering family. A historical brand list or a matching serial shape alone is insufficient.
Reading your result
Master Plumber lookup questions
Why does the year code match more than one year?
Some systems reuse letters or only encode the last one or two year digits. Every supported interpretation is retained. A decade supplied from reliable records can narrow the reading; the tool does not automatically pick the newest year.
Does the serial identify my exact model?
Usually the model is a separate plate field. Where published serial ranges actually identify a model, the result shows model candidates and links to their manuals. Overlapping ranges remain ambiguous.
Can I share the result?
After a lookup, the address includes the serial in a fragment beginning with #serial=. Use “Copy share link” to share the serial and selected context. Opening the link runs the same lookup. The fragment is not a query-string result page.