I'm assuming you've actually tried both methods, judging by your comprehensive post.The spray from your wand hits the carpet for a second at most, cleaning dishes or clothes requires them to be submerged in water and the heat for a lot lot longer, that's the difference, heat requires sustained time to work, which it doesn't get much of with carpet carpet cleaning.
If you want a fairer test spray a really dirty dried in grease ridden dish or jumper with your carpet wand with steaming hot water and then cold water for just one second, the difference is slight at best.
It's fair to say though heat brings a difference, its not huge like people seem to think, were kinda conditioned to think it makes a big difference from a a young age, and from people selling tm's and chemicals that need heat to activate.
Drying times are also improved but again you cant compare a dish with a flat surface to a carpet, both will dry differently with hot and cold. the dish will always dry more efficiently as flat surfaces have more access to air than water under threads of a carpet.
The debate will always rage on![]()

I have a cold water petrol pressure washer and now of course, the Zeta. I can tell you that the hot water definitely cleans my patio more effectively....
Does anyone want to buy a cold water pressure washer..... £60?

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Personally I think a propane burner would be better.


