How to Clean a Bunn Coffee Pot. Cleaning a coffee maker is a necessary task that should be performed at least a few times a year. Determining if a coffee pot needs cleaning is easy to do, either the coffee made will begin to taste bad or the pot will show visible signs of stains and mineral build up. If a Bunn coffee pot is starting to indicate it is cleaning time, a few simple steps are all that is needed to get the coffee pot back to tip-top shape. This routine cleaning will not only assure great tasting coffee, but it will keep the Bunn Coffee maker in good working condition.