Age-decoding methodology
Rules are stored by manufacturer, appliance family and effective production period. Results show the decoded date, confidence and any plausible alternative cycle when a date code repeats over time. The model number is used to narrow out impossible dates.
Error-code methodology
Codes are tied to brand, appliance type and model family. Each guide separates the code definition from likely causes. Safety guidance is conservative and never instructs users to bypass interlocks or work on energized equipment.
Cost methodology
Price ranges combine diagnostic/service charges, estimated labor time, representative parts prices and regional multipliers. Every estimate shows the date of the underlying pricing data and what is included.
Review and corrections
Indexable technical content carries a named author or editorial team, a reviewer identity, and a “last reviewed” date. Material changes update the reviewed date; cosmetic edits do not. See our correction policy.