I happen to like bonnet cleaning.
I especially like it as an additional procedure to a normal extraction.
Bonnet cleaning involves putting a cotton pad on a low speed rotating floor machine and buffing the carpet just like you would burnish (see other post) a tile floor.
You prep the carpet by putting a traffic lane spotter on the soiled areas of the carpet and keep the pad wet so the friction of pad on carpet doesn’t bring the process to a dead stop.
The knock on bonnet cleaning is that it’s an interim process – it makes the top of the carpet fibers clean, but doesn’t do anything for the soil trapped in the lower layers and pad (if any).
So what ?
The procedure can be done very quickly with equipment that is available in most buildings and leaves the carpet dry so it can be walked on the next day.
It’s also a good way to immediately remove spots.
The only real negative is that if you use to much chemical you will make the restorative procedure (extraction) a little more time consuming, and can lead to the same “browning” you get if you use too much chemical in an extraction.
Too much detergent will also lead to “resoiling” – since the detergent attracts soil to itself as a necessary part of the cleaning process, it will also continue to attract soil when left in the carpet.
As an additional procedure in an extraction, it’s an excellent way to get “agitation” – one of the four variables in successful carpet cleaning without having to use a more abrasive carpet brush. A good bonneting will thoroughly mix the emulsifying detergent or solvent with the soil we are trying to remove – improving the outcome of the extraction without having to either oversoak the carpet or do repeated passes with the extractor to attain the same degree of emulsification.