| E Z Peaces 2008-02-07, 5:25 pm |
| Charles Self wrote:
> OK, here's the pitch: here in Germany all washing machines have
> heating rods which heat the washwater to temperatures from 20 to 95° C
> (= 70-200° F), with most of the washing done at 30 or 60° C (90-140°
> F).
> The other day I heard a radio feature that most modern detergents work
> well already at 20° C (i. e. normal room temperature), that the notion
> that only hot washes were thorough was antiquated, and so much so that
> in many parts of the world, such as Australia or the US, washing
> machines wouldn't even possess heating rods at all, and just used
> water at tap temperature.
> So is that the truth, Ruth?
> I'd specifically like to hear from Yanks and Ozzies, thanks.
Sometimes hot water is required to bring wash water up to room
temperature (20 C). That's warm enough for some items, but detergent
manufacturers may define Cold as 82 F (28 C).
For most items, American detergents work well at Warm. Body
temperature, 99 F (37 C) is ideal. Many detergents contain enzymes that
work best at that temperature. My washing machine doesn't have a
heater, but it has a computer to mix water at about 99 F.
Hot washes are usually for whites. I used oxygen bleach (sodium
percarbonate) for a dress shirt that had yellowed badly in a closet.
Without enzymes, oxygen bleach works best above 140 F (60 C). My
household water isn't that hot. I soaked it in a pan on the stove at
150 F, using a potato masher to agitate. It came out clean and wrinkled.
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