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critical Keurig
Error Code 6
The Preheat Tank thermistor reading is below 37°F and the heater will not turn on to protect against damage.
? What Causes This
The brewer was stored at cold temperature or the thermistor is faulty.
✓ How to Fix It
Allow the brewer to warm to room temperature for at least two hours before powering on. If the issue persists, the thermistor may be faulty and you should contact your Keurig Authorized Distributor.
Source: page 16 of the official manual
From the manual
This error code appears in:
Keurig Coffee Maker