Troubleshooting your coffee maker before you've had your cup of coffee can be frustrating. Let's dig into this troubleshooting guide to get your morning cup brewing and start the day off right.
While this guide is focused first on automatic drip coffee makers, a good starting procedure for any device is to follow proper maintenance and cleaning practices — follow this coffee maker cleaning guide and replace old filters.
If using soft water, clean your machine with a 1:1 vinegar and water solution every 3 months; with hard water, every 1 month.
Misalignment of Parts
Verify that the coffee pot, lid, filter, and filter cover are all nested in their correct positions. The coffee maker may have safety settings that prevent the brew from starting. Also, make sure your machine is not empty and is filled with clean water.
While regular cleaning helps prevent mineral clogging, buildup may still occur. Remove your bottom plate to access the water lines. The hoses can then be removed and visually inspected for buildup. Clean with soap and water and a small brush.
This is time to inspect the ball valve. This valve allows fluid to move forwards but not backwards, and can be tested in two ways. Shaking the valve will tell you if the ball is free and is a good sign it's functioning. If you remove the valve and can only blow air in one direction, the valve still works. If you cannot blow in either direction, clean the ball, and reassemble the valve.
Broken Thermostat or Blown Thermal Fuse
The thermostat is a safety switch which electronically energizes the heating element while there's water in the tank, and disconnects or opens the circuit after the water is gone and it's only heating itself. Unplug your machine, grab a multimeter, and open the bottom cover. If the thermostat continuity tests at room test between 0-1 Ohm (Ω) then it doesn't need replacing.
Find and test the inline thermal fuses. The fuse is a safety device designed to fail in the event of a runaway thermostat. In the event of a blown fuse or open circuit no power will reach the heating element and your coffeemaker will not brew. If either fuse tests outside of 0-1Ω, replace the fuse by installing another in parallel.