Another method after you have vacuumed the front is to put a shallow baking tray under the coils, take a Yard Sprayer with water, pump up the pressure and spray the coils clean. A few drops of soap in the sprayer can be used. The tray on the bottom will collect the dirt and water. Empty as necessary, and be sure to unplug the unit FIRST ! If you don't have a Yard Sprayer use a Windex Cleaner type sprayer.
I have / had a great running /performing OBD merchandiser (half the size of the unit in this video) and I dollied it outside to clean it (although it was not very dusty at all) and after using a 150 psi air compressor to completely blow out every spec of dust ... the condenser does not engage/cool. What is the likely culprit (a loose wire?) as the unit worked perfectly before I decided to perform my routine maintenance.
About what your saying with cleaning with compressed air or nitrogen, sure blowing into the face of the condenser is extremely stupid, but what we do is pull the condensers out where we have access to fan side and blow it out with a wet rag over face to catch debris... we also finish with a vacuum to clean up any final debris, imo the nitrogen technique is the best way to clear out a condennsser without washing it.
