Judging the blockage of the smoke exhaust pipe of the coffee roaster and the method of checking and cleaning

For professional coffee roasting, tube blockage is always a headache. When the coffee beans are baked, they produce soot. This soot is not only exhaust gas, but also contains a lot of silver dandruff and dirt impurities of raw beans. As long as the coffee roaster machine keeps running, it is full of impurities and dander. The soot will be produced and discharged continuously,   and the highly viscous soot will gradually adhere to the surface of the object to be contacted, and will proliferate and thicken, eventually causing blockage of the exhaust line. Blocking doesn’t have to wait until your tubing is completely blocked. As long as it accumulates to a certain thickness, it has greatly affected the baking quality of the coffee beans and the performance in the cup.
Blocking of coffee roaster machine can occur at any point, from the damper, fan blades, dust buckets, electrostatic machines, to any point in the exhaust path! Often you think that the clean place is all noticed, and blocking may still happen in unexpected places. Severe blockage will cause all the baking data to fail, and some of the tastes will not come out. The taste that should not be there is uninvited, making your daily coffee baking work becomes a nightmare.


How do we detect the occurrence of a blocking of coffee roaster machine ? When you find that one or more of the symptoms appear, blocking may have happened!

  1. The heating rate deviates from normal, the middle section of the baking begins to heat up faster than usual, and the deviation from the tail section is larger.
  2. It has a sweet taste but it smells like a layer of fog.
  3. Lack of clean brightness, which tends to be either: sweet and dull mouthfeel or strong acidity on both sides of the tongue.
  4. Some of the aromas are grinded up (dry aroma) can be smelt but can’t be tasted
  5. With a salty taste, the plot varies from very small to very obvious. Salty taste can be easily detected using Espresso Cupping.
  6. Unclean smell or astringency appears.

Coffee roasting machine

What should we do with the coffee roaster machine if we find that there may be symptoms of tube blockage? Here are the cleaning steps you should take:

  1. Immediately stop working and turn off the flame until the roaster is completely cooled to room temperature.
  2. Take down and take out all the exhaust pipe paths, and gradually confirm whether the following units are blocked: the roaster body (exhaust path, damper, fan blades), dust bucket (upper, middle, funnel), all Duct path (especially where the turning or caliber changes), electrostatic machine (inlet and outlet, filter, plate, fan), outdoor chimney pipe. All places where the exhaust gas passes will need to be removed for inspection.
  3. The blockage and hyperplasia of the dander should be thoroughly cleaned regardless of the severity of the plot.
  4. After the installation is gone, the zero-baked baking test program is performed, and the new baking data is recorded according to the result of the zero-return test.
  5. Set the baking counter, return to zero and start recording the number of baking ovens after cleaning.
  6. During the cleaning operation, it is possible to use a towel that does not depilate, avoid using a hard brush, and pay attention to the integrity of the rubber band in the joint during installation.