come on Nick,
you were just being smart arse weren't you
pH = potential/possibility of Hydrogen
99.9% of us are carpet cleaners and not chemists or scientists and only need to understand the basics of pH. well thats my excuse any way
The manufacturers have done all the work for you with regard to dilution rates,dwell times, etc.
So unless you carry a lab around with you in the back of your van, you should not be altering mixing ratios already tried and tested by the manufacturers in your cleaning process.If you do and come unstuck as a result ie browning then its your responsibility.
As for acid rinses, a lot of cleaners carry this out as a matter of course and most times it is simply not required indeed if you do and it's not required you could do what you were trying not to do which is push the carpet out of its safe pH range.
It must be remembered that most carpets are not manufactured at pH neutral 7 but will be around the pH 4 mark for example with the dyes stable up to pH7- 8.If this carpet is then cleaned using a product with a pH of 9 then pH of the carpet will rise from 4 to around 5.5-6 so its still safe.Had the carpet been 7 to start with then the alkaline would rise to 8.5 - 9 and you could now be in trouble as its out of its safe range.Add to that the possibilty that the carpet may have been cleaned in the past and the pH may already be at 8 as the last cleaner had used an alkaline product of 9.He got away with it and left it in its safe range but now you come along and clean again at pH 9.The carpet is now at pH 9-10, your in trouble with out even realising it.
You must also of course make sure you know when using alkaline products if they are buffered or not.
If you have the above information you would then know when to use a sour rinse or not.For example if you don't know if the carpet had been previously cleaned then it might be a good idea to protect yourself and carry it out( if you haven't already carried out a pH test that is which of course we all know we should if no information is to hand
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