Ill kick you too Bob, but only as a lesson to all those oxidizer-everything freaks that claim they've never done any damage.
“I hear all kinds of different things about wool from "be very careful" to "it’s tough of nails" and people really don't need to be overly concerned with it if they follow a few basic rules.” … “I'm not talking about rugs here; I'm specifically referring to installed wool or wool blend broadloom.”
Pretty easy to work with if you follow those rules: Keep the heat down on deep colored or patterned/colored wool carpet for the sake of the dye; a higher pH can be used if it isn’t buffered to retain that high pH. (I believe that a buffered “8” pH product can be cumulatively worse than an unbuffered “10” pH); oxidizers should only be used a last resort. The damage may not be apparent to you, but it is happening.
“So today's job which I previewed last week has an obvious need for a re-stretch. But this is very common on wool…”
Carpet pile has nothing to do with installation. Jute backed carpet should be installed just like polypropylene, but sometimes installers will cheat, knee-kick the jute-backed carpet and then water it with a watering can to make it shrink enough to remove ripples. Poorly installed wool carpet is not common here, so maybe your neighborhood had a high-end retailer with a lazy installer.
“Presprayed with Judson Juice pH 8.something. Laid it on fairly normally (well maybe a little heavy)”
Is that a buffered “8”? If so, don’t use it on wool.
Kicked it with a powdered peroxide because it had some spots that could use it. Besides it was a really light colored carpet. Done it lots of time on wool.
This is a very bad habit. You’ve been lucky in the past, so maybe this is Karma. Ever seen frizz-headed bleached blondes? That's oxidizer damage, and their hair is continuing to grow out. The carpet doesn't have a chance.
Oxidizers lift the wool cuticle and promote felting and they chemically burn the fiber. If the wool turns yellow from over-use of oxidizer, using more to correct the problem will result in the yellow returning faster than it did before and often it becomes darker – even brown. Sometimes the use of a strong acid will cure the problem until the next cleaning, but the damage is done.
(Very often poor quality sheepskins will be treated with an oxidizer to whiten them for sale; then they rapidly turn yellow.)
Extracted pretty hot (with an acid rinse).
Good move. If done quickly enough after cleaning it could stop damage before it gets bad.
Browning and big circles from previous land mines that look like watermark circles. These were areas the owner pointed out to me before I started and there were brown stains under the glass where condensate had run down from the windows and left the carpet damp. Plus the cat had a few accidents. But I start to look closer and start to see what I think is some of this carpet is browning out.
The reason the land mines of spots were in the carpet is because everyone else never cleaned it with the same heavy process I did. Note I said heavy process and not better process.
Your guess might be right, but I’d guess this may have had more to do with the land mine and not poor cleaning by someone else. You know that people will blot spills and get them to wick into their blotting material, leaving lots of residue at the base to wick up when the carpet is cleaned. Homeowners often chemically burn their own carpet by pouring baking soda or table salt on pet stains. As you wet rinse these areas the alkalinity of the baking soda starts to show the damage done to the carpet. This is akin to spilled Comet or Ajax on a bathroom carpet; there is little you can do to know this is there.
Adding an alkaline cleaner with a “kick” of peroxide adds to the burn.
Lessons learned that I knew but should have paid close attention too.
3. Never shoot jute with too much moisture either with the pre-spray or extraction process. - I full keyed this job at 500 psi - DUMB MOVE and as I said I put the pre-spray on a bit heavy. So, the damn thing yellowed because of too much moisture in spite of first class pre-spray and rinse.
Wool doesn’t yellow due to being over-wet.
Extract with an acid rinse low pressure and dry stoke the crap out of it and put the fans on it to speed dry it. If I have to, I'll post pad it and all should be good.
Post padding will only help if the problem is wicking, which it seems might be the problem under the window. If the problem is an alkaline burn, use a strong acid that you can leave in the carpet (no sticky residue). You may have to use something as strong as hydrofluoric if you can find some. Hiding everything with a coat of primer/encap might be an option; the owner can replace the carpet the next time it needs cleaning.
As for the Dyson it was my understanding that WoolSafe NZ had a warning specifically directed at the Dyson vacuum. But according to this WS website they are listed as approved.
Unfortunately, WoNZ never tried to make their certification program into a cash cow and lost out to Woolsafe, which is rapidly attaining a CRI level of credibility.
PS: Did I forgert to say that none of this may have anything to do with your cleaning process? Oops!
We once cleaned at a very high-end home of a long-term customer. Everything was great except the white wool in the guest bedroom. We got called back because it had browned, and the tech called me to come and look at it as soon as he arrived. The entire rug had severe stripes of browning and an area the tech had test cleaned got better but not great. After much questioning the homeowner admitted "touching up" the guest room with her Kirby home carpet cleaning machine and laundry detergent. She may have used a little bleach too.
The carpet was more heavily soiled than the rest of the house when the tech first arrived, but there was no sign of the damage until several hours after our very appropriate-for-wool cleaning.
