I'm not against using "fabric softener" as a defoamer substitute when in a pinch. If it's going to help protect my carpet cleaning equipment from costly repairs I'm all for it.

But, we have learned that it's best to use products specifically designed for carpet cleaning, including defoamers recommended by the equipment manufacturer or cleaning product supplier. These products are formulated to work effectively without causing any adverse effects on the carpet or the cleaning equipment.

Do you clean a load of laundry using no soap?

 

Some have commented that the softener chemistry affects the emulsification process if used as a prespray or applied to the carpet while cleaning but if there is already an over use of detergents the dirt and oils are already suspended in the dried surfactants and just need to be rinsed out as efficiently as possible so I say go ahead and prespray away as long as you know that you are dealing with this over foaming situation.  

I was doing hotel rooms where previous "in house cleaning" crews constantly over applied and never rinsed properly the sudzy bubbles from the carpet. This dogged down the whole cleaning process for me.  

I was once told that the old fashioned urinal cakes used in typical gas station bathrooms would melt down foam in the waste tank really well but besides the overpowering odor exhausted these cakes (made from the same compounds as mothballs) were toxic to breathe (carcinogenic) and are now banned by the janitorial industries. 

And so we just keep searching for the best solutions. I say learn on....      

I would also recommend some chemical De-Foamers for extreme cases. They are more expensive but your will make sure your job doesn't get delayed or have any issues. The amount of money you could lose if a job didn't get completed is much smaller than the cost of these products.

I use both sea salt and chemicals, depending on the situation.

Sammy