How Warm is Warm Water, How Cool is Cool, How Hot is Hot? Range of Values

<...how cool is cool for cool water...>

Evaporative cooling towers cannot operate at lower temperatures than the wet-bulb temperature of the air passing through them.

You might as well ask "How high is the sky?" There will always be a wide variation depending on everything from local ordinance codes to the time of day will change all of these temperatures. The hot water supply for a coffee bean processing facility will certainly be different than the hot water for a sewage processing plant. Then you can get into the more exotic processing plants like nuclear power stations where some hot water circuit temperatures will greatly exceed the steam temperature of other water circuits.

That's why I tell people "No, I can't make your refrigerator colder. You tell me the temp you want and I will tell you if I can make it do it." -- JHF

Hot, cold, warm, cool, high, low are all adjectives and are relative terms they do not have a fix temperature. If you need to know what temperature they are you should ask at the source that provides them. Only they can give you a definitive answer.

I did see one once relating to temperature as observed by the naked eye and experienced by touch (it was in relation to metalworking). Again it is very subjective and not very practical (especially not for process control).

I would suggest actually monitoring and controlling the temperature (in deg. C or F).

westdeap12-

Perhaps a "rule of thumb" I was once taught can help you. Yes, there are not volumes of extensive research and calculations to verify this, just something a chemistry prof once taught his class when presented with a similar question:

Use the metric system with Celsius temperatures; 0 (32F) is freezing; 0-10 (32-50F) is cold; 10-20 (50-68F) is cool; 20-30 (68-86F) is warm; 30-40 (86-104F) is hot; 40-50 (104-122F) is very hot; 50-60 (122-140F) is extremely hot.

In processing plants its more a matter or relatively. The coldest is the cold one vs. the warm one which is the next warmer than the cold one vs. the hot one which is the one warmer than the warm one, etc.

With pressure its also a matter of relativity but sometimes professional or legal standards become a determination.

Good Luck, Old Salt

You got the zero degrees C correct at least.

As has been pointed out the description is quite process specific.

As stated-

In processing plants its more a matter or relatively. The coldest is the cold one vs. the warm one which is the next warmer than the cold one vs. the hot one which is the one warmer than the warm one, etc.

With pressure its also a matter of relativity but sometimes professional or legal standards become a determination.

In one environment one temperature such as 60^oF can be hot but in another it can be extremely cold. It all depends upon what you are comparing it with!

Old Salt

I like it.

However, my wife would probably not agree that 68 to 86 is warm. To her anything below 80 deg is cold. And for some reason my telling her to put on a sweater instead of turning up the thermostat seems to make the room colder.

Uh, uh. Sounds familiar . . .

peterq7lyg-

I once had the pleasure of meeting Mr. Einstein, his spelling and composition was also at about the same level as mine. Despite our deficiencies, we were still able to hold a relatively interesting conversation. At that time he was "an old man" and I was "a young kid".

"In processing plants its more a matter of or relatively."

"To err is human, to forgive devine"

Old Salt

all gave good answers. well, rule of thumb and human senses give surely give more accurate answers. form the functional despcription and plant manual doesn not provide enough info. currently, not even the piping system is up yet on the building.

There is no scale to relation or relative term. Example 68 deg. F is cool water in relation to 100 deg. Nomenclature "COOL" would not exist when there is no water of tempt 100 deg. The same water 68 deg is warm water/hot water in relation to 58 deg F. Therefore no international standard demography can be made to the relative nomenclature.

Polish Daniel Gabriel Fahrenheit (1686-1736), Swed Astronomer Anders Celsius (1701-1744), British Physicist William John Macquorn Rankine (1820-1872) and Scotish Sir William Thompson Kelvin (1824-1907), in that ascending chronology, have given clues to this 3-4 centuries ago.

Since no frame of reference has been chosen or identified, cool, warm and hot are relative terms. At 1 atmosphere, All allotropes of Iron (α, γ and δ) melt between 700 and 1400ºC depending on the impurities or ballasts whereas pure water tripple point occurs at 0ºC and waxes, despite belonging to the same group do this at different temperatures. Boiling water temperature (100ºC) is a cool condition for Iron. That water evaporates at any temperature makes the answer more flexible. Are lyophilization processes at temperatures below 0ºC not a proof of this relativity? Thinking of this without reference point will set one on convoluted motion!

Hi West,

After my hands and body, including shower, I can say the water is cold between 10 to 20*C. Between 20 to 55*C is warm, and above 60*C is hot. There is no technical or scientific approval of this personal appreciation of water, just my definition when I am in contact with it, Gil.

Don't know if this helps but the recommended temperature of hand washing water is 40° ±3°C (~98-110°F) That may cover "warm"????