Clogged lines are always a headache for professional coffee roasters. When coffee beans are roasted, soot will be produced. This soot is not just exhaust gas, but also mixed with a lot of silver dandruff and dust impurities from green beans. As long as the coffee roaster continues to operate, this kind of fume full of impurities and dander oil fume will be continuously produced and discharged, and highly viscous oil fume dander will gradually adhere to the surface of the object in contact, and proliferate and thicken, eventually causing the blockage of the exhaust pipe. Blockage does not need to wait until your pipeline is completely blocked, as long as it accumulates to a certain thickness, it is enough to greatly affect the roasting quality of coffee beans and the performance of the cup.
Blockage may occur in any link, from dampers, fan blades, dust buckets, and electrostatic machines, to any part of the smoke exhaust path! Often you have noticed all the places you thought should be cleaned, but clogging may still occur in unexpected places. Severe blockage will cause all your roasting data to fail, the taste you should have will not come out, and the taste you shouldn’t have will come uninvited, making your daily coffee roasting work a nightmare.
How to detect the occurrence of a blocking situation? When you notice one or more of the following symptoms, the blockage may have occurred!
1. The heating rate deviates from normal, the temperature rises faster than usual in the middle of the baking, and the deviation is greater at the end.
2. It has a sweet taste but tastes like a layer of fog.
3. Lack of clean brightness, leaning towards one of the following: sweet blunt mouthfeel or strong acidity that appears on both sides of the tongue.
4. Some aromas can be smelled after grinding (dry aroma), but cannot be drunk in the mouth.
5. It has a salty taste, ranging from very slight to very obvious. Saltiness is easily measured with Espresso Cupping.
6. Unclean miscellaneous or astringent taste appears.
What should we do when we find that there may be symptoms of pipeline obstruction? Here are the cleanup steps you should take:
1. Immediately shut down and turn off the flame, and wait until the roaster is completely cooled to room temperature.
2. Remove all the smoke exhaust pipe paths, and gradually confirm whether the following units are blocked: the roaster body (exhaust path, inside the damper, fan blades), dust collection bucket (upper layer, middle layer, around the funnel), all air duct path (especially the turning point or caliber change point), electrostatic machine (air inlet and outlet, filter screen, plate, exhaust fan), outdoor chimney pipe. All places where the exhaust gas will pass need to be dismantled and inspected.
3. Thoroughly clean the places where the blockage and dandruff proliferate, regardless of the seriousness of the case.
4. After installing it back, carry out the zero-return roasting test procedure, and record the new roasting data according to the result of the zero-return test.
5. Set the roasting counter, reset it to zero, and start recording the number of roasting ovens after cleaning.
6. During the cleaning operation, it is possible to use a non-shedding towel, avoid using a hard brush, and pay attention to the integrity of the rubber ring at the link during installation.