Reliability Reporting of Consumables in a Consumer-Maintained Durable Product

Durable products often have a replaceable element, that has a life significantly shorter than the system into which it is installed. The type of replaceable component treated in this paper is purchased and installed by the customer. These components may be a filter, a lamp, an ink cartridge etc. In recent years, these components contain electronics that interact with the main system. When they fail they need to be diagnosed and repaired or replaced which affects warranty costs. Inherently, the customer performing the installation and replacement do not track or submit the date of installation or purchase. Many times, the customer will purchase multiple replacements to be used in future years. Because sales of replacement parts are much greater than sales of the main units, there are compelling financial reasons to track, and improve the reliability of the consumable product as well as understand any unreliability. Unfortunately, without knowing when the product was installed it is difficult to calculate the `time to failure' which is necessary for any analysis of reliability. Presented here are three ways to track and predict the reliability of these replaceable and consumable products, how to understand their unreliability using a computer model, and calculate the attrition of main units in the field.