The right and wrong way to cleaning kitchen exhaust systems
Here, I will go over what I feel is the right to clean a hood system. The first step is the setup. Remove all items from the cooking equipment. and turn off the pilot light. Drape plastic sheeting over the equipment or setup a funnel to have all the water fall into a barrel. Note that every system can be set up with a funnel.
Once the cooking equipment is covered properly, we now contain the area. Drape plastic from as high of a point as possible, hopefully the ceiling, down to three inches above the floor in front of the cooking equipment. This will prevent any back splashes of water from contaminating your kitchen.
The next step is to remove the grease filters from your kitchen exhaust system and place them wherever you are going to be cleaning them. If possible, soak them in a chemical solution to assist the cleaning when we get to that stage.
Now that you are set up, check for panels. If there are any panels, open them and scrape out any heavy grease. Also do this to the hood itself.
Now, go to where the fan is located, typically on the roof. However, the fan may also be located on the side of your building. One person stays at the hood armed with a shop vac ready to suck up the water. Then flip the fan to expose the ductwork and the fan blades. You should note that every fan has a hinge hook set up specifically for this purpose.
Once the fan is flipped, the action begins. The ductwork and fan blades are degreased and power washed. Then the fan is placed back. The inner part of the top of the fan is now degreased and power washed. All this happens while water is falling down your ductwork at a rate of between 2 to 5 gallons of water per minute depending on the equipment being used. The man on the ground inside your kitchen takes care of that as it falls. Teamwork is crucial in this work!
Once the fan and duct have been cleaned properly, it is time to move on to the kitchen hood. Move your equipment and yourself to the ground and then degrease and power wash the hood as necessary to make it clean. Sometimes, scrubbing with steel wool and scraping with stiff heavy metal scrapers is required.
Once the hood is clean, one person dries the water from the hood with a towel and polish the hood with steel shiner while the other person goes to tackle the filters. The filters are degreased and power washed, the back side first and then the front. When this is done, put the filters back in your shiny clean kitchen exhaust system and clean up all the mess. Collect payment and leave.