Keurig coffee makers can malfunction because of many issues, including mineral deposits, clogged water lines and maligned water reservoirs, reports KCupBarista.com. Keurig coffee makers contain many small moving parts which require maintenance and sometimes repair.
A common issue with Keurig coffee makers is a maligned water reservoir. The reservoir has a small magnet on the bottom which aligns with a sensor within the coffee brewer. When this is out of line, the machine thinks the reservoir is not attached and thus does not brew. Removing the reservoir and putting it back into the machine usually solves this issue.
Water lines in the machine get clogged from time to time. Running the brewer without a Kcup for several cycles remedies this issue.
Mineral deposits can cause problems with brewing. A malfunctioning Keurig may need to be descaled through the use of a chemical solution. Vinegar can be used in stead of a descaling solution, adds CoffeeHouse Express. The machine should be run with vinegar in the reservoir, after which the vinegar should be left in the system for four hours before rinsing. Deposits in the main needle of the machine can be removed with a paper clip or other small object.
Some Keurigs sold in 2009 and 2010 had pump issues, resulting in low pressure and brewing difficulties. This problem is covered by warranty and Keurig normally replaces these models.