Is this cheap “air conditioner” able to cool a room?On a hot day, when it's cooler outside than in; is it better to put a fan in an open window pointing inwards or outwards?If fans increase the heat of the air and this DIY AC decreases it, why don't they neutralize eachother?Would using a fan cause an air conditioning system to think it's cold?Single story, hotter outside, some shade from porch, enough to cool house with/without air flowing?Effect of “fan speed” setting on air conditioner efficiencyShouldn't turning the air conditioner off during the day save energy?Which is a more efficient method of heat transfer?How to maximize the efficiency of a portable air conditioner?Relationship between Specific heat capacity and Newton's law of coolingHow does an ultrasonic humidifier / atomizer affect temperature?
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Is this cheap “air conditioner” able to cool a room?
On a hot day, when it's cooler outside than in; is it better to put a fan in an open window pointing inwards or outwards?If fans increase the heat of the air and this DIY AC decreases it, why don't they neutralize eachother?Would using a fan cause an air conditioning system to think it's cold?Single story, hotter outside, some shade from porch, enough to cool house with/without air flowing?Effect of “fan speed” setting on air conditioner efficiencyShouldn't turning the air conditioner off during the day save energy?Which is a more efficient method of heat transfer?How to maximize the efficiency of a portable air conditioner?Relationship between Specific heat capacity and Newton's law of coolingHow does an ultrasonic humidifier / atomizer affect temperature?
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;
$begingroup$
My parents bought this "air conditioner", but I am very skeptical that this can cool a room, or even cool anything.
I doubt that it even has a cooling element, I suspect that it is just a fan + humidifier.
But even if this device had a cooling element, it still couldn't cool a room:
If air is cooled, the resulting heat can't just vanish, it has to go somewhere, because of the 1st law of thermodynamics (energy conservation). In a normal full-sized air conditioner, the air is cooled and the resulting hot air is blown outside. But in this mini "air conditioner", the heat cant go outside, it can only stay in the room, keeping the room at the same temperature.
Am I missing something or is this a scam as I suspected?
thermodynamics energy-conservation air cooling fan
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
|
show 3 more comments
$begingroup$
My parents bought this "air conditioner", but I am very skeptical that this can cool a room, or even cool anything.
I doubt that it even has a cooling element, I suspect that it is just a fan + humidifier.
But even if this device had a cooling element, it still couldn't cool a room:
If air is cooled, the resulting heat can't just vanish, it has to go somewhere, because of the 1st law of thermodynamics (energy conservation). In a normal full-sized air conditioner, the air is cooled and the resulting hot air is blown outside. But in this mini "air conditioner", the heat cant go outside, it can only stay in the room, keeping the room at the same temperature.
Am I missing something or is this a scam as I suspected?
thermodynamics energy-conservation air cooling fan
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
$begingroup$
I saw a web based advert for something like this. It was pointed out to me and my immediate comment was the thermal energy pumped must go somewhere. Normally it is sent outside. I then figured this must just be a fan that blows air over ice or dry ice or something. The actual refrigeration may not be done by this unit.
$endgroup$
– Lawrence B. Crowell
9 hours ago
5
$begingroup$
Looks like a toy, but a larger-sized version of the same thing sometimes is known as a swamp cooler They work well in dry climates: It takes energy to make water evaporate. Water exposed to dry air will evaporate, and the vapor and the water will become cooler than the ambient air as a result. en.wikipedia.org/wiki/Enthalpy_of_vaporization
$endgroup$
– Solomon Slow
9 hours ago
1
$begingroup$
Having lived with swamp coolers as my primary cooling system for a number of years, I can attest that (A) thy work very well in dry places like southern New Mexico and (B) on the few humid days a year you either suffer or retreat to a place that has refrigerated air.
$endgroup$
– dmckee♦
9 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
Starting from, say, 40 C and 10% RH (a nice summer day in the area where I lived with these thing) you'd get about 15 C cooling. Performance drops rapidly with increasing humidity and slowly with decreasing exterior temperature. But beware that a unit sized for a small building is an appreciable fraction of a cubic meter in size and the fan makes a lot of noise. Even in the places where they work well these things are understood to be a cheaper alternative to a real refrigeration unit: something you use if you can't afford the better option.
$endgroup$
– dmckee♦
7 hours ago
|
show 3 more comments
$begingroup$
My parents bought this "air conditioner", but I am very skeptical that this can cool a room, or even cool anything.
I doubt that it even has a cooling element, I suspect that it is just a fan + humidifier.
But even if this device had a cooling element, it still couldn't cool a room:
If air is cooled, the resulting heat can't just vanish, it has to go somewhere, because of the 1st law of thermodynamics (energy conservation). In a normal full-sized air conditioner, the air is cooled and the resulting hot air is blown outside. But in this mini "air conditioner", the heat cant go outside, it can only stay in the room, keeping the room at the same temperature.
Am I missing something or is this a scam as I suspected?
thermodynamics energy-conservation air cooling fan
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
My parents bought this "air conditioner", but I am very skeptical that this can cool a room, or even cool anything.
I doubt that it even has a cooling element, I suspect that it is just a fan + humidifier.
But even if this device had a cooling element, it still couldn't cool a room:
If air is cooled, the resulting heat can't just vanish, it has to go somewhere, because of the 1st law of thermodynamics (energy conservation). In a normal full-sized air conditioner, the air is cooled and the resulting hot air is blown outside. But in this mini "air conditioner", the heat cant go outside, it can only stay in the room, keeping the room at the same temperature.
Am I missing something or is this a scam as I suspected?
thermodynamics energy-conservation air cooling fan
thermodynamics energy-conservation air cooling fan
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
edited 4 hours ago
xray0
4803 silver badges16 bronze badges
4803 silver badges16 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
asked 9 hours ago
SinOfficialSinOfficial
1134 bronze badges
1134 bronze badges
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
SinOfficial is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$begingroup$
I saw a web based advert for something like this. It was pointed out to me and my immediate comment was the thermal energy pumped must go somewhere. Normally it is sent outside. I then figured this must just be a fan that blows air over ice or dry ice or something. The actual refrigeration may not be done by this unit.
$endgroup$
– Lawrence B. Crowell
9 hours ago
5
$begingroup$
Looks like a toy, but a larger-sized version of the same thing sometimes is known as a swamp cooler They work well in dry climates: It takes energy to make water evaporate. Water exposed to dry air will evaporate, and the vapor and the water will become cooler than the ambient air as a result. en.wikipedia.org/wiki/Enthalpy_of_vaporization
$endgroup$
– Solomon Slow
9 hours ago
1
$begingroup$
Having lived with swamp coolers as my primary cooling system for a number of years, I can attest that (A) thy work very well in dry places like southern New Mexico and (B) on the few humid days a year you either suffer or retreat to a place that has refrigerated air.
$endgroup$
– dmckee♦
9 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
Starting from, say, 40 C and 10% RH (a nice summer day in the area where I lived with these thing) you'd get about 15 C cooling. Performance drops rapidly with increasing humidity and slowly with decreasing exterior temperature. But beware that a unit sized for a small building is an appreciable fraction of a cubic meter in size and the fan makes a lot of noise. Even in the places where they work well these things are understood to be a cheaper alternative to a real refrigeration unit: something you use if you can't afford the better option.
$endgroup$
– dmckee♦
7 hours ago
|
show 3 more comments
$begingroup$
I saw a web based advert for something like this. It was pointed out to me and my immediate comment was the thermal energy pumped must go somewhere. Normally it is sent outside. I then figured this must just be a fan that blows air over ice or dry ice or something. The actual refrigeration may not be done by this unit.
$endgroup$
– Lawrence B. Crowell
9 hours ago
5
$begingroup$
Looks like a toy, but a larger-sized version of the same thing sometimes is known as a swamp cooler They work well in dry climates: It takes energy to make water evaporate. Water exposed to dry air will evaporate, and the vapor and the water will become cooler than the ambient air as a result. en.wikipedia.org/wiki/Enthalpy_of_vaporization
$endgroup$
– Solomon Slow
9 hours ago
1
$begingroup$
Having lived with swamp coolers as my primary cooling system for a number of years, I can attest that (A) thy work very well in dry places like southern New Mexico and (B) on the few humid days a year you either suffer or retreat to a place that has refrigerated air.
$endgroup$
– dmckee♦
9 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
Starting from, say, 40 C and 10% RH (a nice summer day in the area where I lived with these thing) you'd get about 15 C cooling. Performance drops rapidly with increasing humidity and slowly with decreasing exterior temperature. But beware that a unit sized for a small building is an appreciable fraction of a cubic meter in size and the fan makes a lot of noise. Even in the places where they work well these things are understood to be a cheaper alternative to a real refrigeration unit: something you use if you can't afford the better option.
$endgroup$
– dmckee♦
7 hours ago
$begingroup$
I saw a web based advert for something like this. It was pointed out to me and my immediate comment was the thermal energy pumped must go somewhere. Normally it is sent outside. I then figured this must just be a fan that blows air over ice or dry ice or something. The actual refrigeration may not be done by this unit.
$endgroup$
– Lawrence B. Crowell
9 hours ago
$begingroup$
I saw a web based advert for something like this. It was pointed out to me and my immediate comment was the thermal energy pumped must go somewhere. Normally it is sent outside. I then figured this must just be a fan that blows air over ice or dry ice or something. The actual refrigeration may not be done by this unit.
$endgroup$
– Lawrence B. Crowell
9 hours ago
5
5
$begingroup$
Looks like a toy, but a larger-sized version of the same thing sometimes is known as a swamp cooler They work well in dry climates: It takes energy to make water evaporate. Water exposed to dry air will evaporate, and the vapor and the water will become cooler than the ambient air as a result. en.wikipedia.org/wiki/Enthalpy_of_vaporization
$endgroup$
– Solomon Slow
9 hours ago
$begingroup$
Looks like a toy, but a larger-sized version of the same thing sometimes is known as a swamp cooler They work well in dry climates: It takes energy to make water evaporate. Water exposed to dry air will evaporate, and the vapor and the water will become cooler than the ambient air as a result. en.wikipedia.org/wiki/Enthalpy_of_vaporization
$endgroup$
– Solomon Slow
9 hours ago
1
1
$begingroup$
Having lived with swamp coolers as my primary cooling system for a number of years, I can attest that (A) thy work very well in dry places like southern New Mexico and (B) on the few humid days a year you either suffer or retreat to a place that has refrigerated air.
$endgroup$
– dmckee♦
9 hours ago
$begingroup$
Having lived with swamp coolers as my primary cooling system for a number of years, I can attest that (A) thy work very well in dry places like southern New Mexico and (B) on the few humid days a year you either suffer or retreat to a place that has refrigerated air.
$endgroup$
– dmckee♦
9 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
2
$begingroup$
Starting from, say, 40 C and 10% RH (a nice summer day in the area where I lived with these thing) you'd get about 15 C cooling. Performance drops rapidly with increasing humidity and slowly with decreasing exterior temperature. But beware that a unit sized for a small building is an appreciable fraction of a cubic meter in size and the fan makes a lot of noise. Even in the places where they work well these things are understood to be a cheaper alternative to a real refrigeration unit: something you use if you can't afford the better option.
$endgroup$
– dmckee♦
7 hours ago
$begingroup$
Starting from, say, 40 C and 10% RH (a nice summer day in the area where I lived with these thing) you'd get about 15 C cooling. Performance drops rapidly with increasing humidity and slowly with decreasing exterior temperature. But beware that a unit sized for a small building is an appreciable fraction of a cubic meter in size and the fan makes a lot of noise. Even in the places where they work well these things are understood to be a cheaper alternative to a real refrigeration unit: something you use if you can't afford the better option.
$endgroup$
– dmckee♦
7 hours ago
|
show 3 more comments
3 Answers
3
active
oldest
votes
$begingroup$
I doubt that it even has a cooling element, i suspect that it is just a fan + humidifier.
The fan+humidifier is the cooling element for this unit. It uses purely evaporative cooling to reduce the temperature of the system. It can do this because the phase change between liquid and vapour requires energy. By just passing a convective current of relatively dry air over a liquid water reservoir, heat is taken from the air to evaporate the water. This results in the humidified air being a lower temperature than before it entered the humidifier.
In this case, the heat doesn't just vanish. The heat lost is stored in the latent heat of vaporization of the water. If the vapour in the room were to begin condensation, the heat in the room would start to increase.
Basically, you're just using the humidity as a sort of thermal battery. You're able to store some of the heat in the room in the form of increased relative humidity, instead of having it go towards increasing temperature directly. The energy doesn't leave the system; it's just taken a different form as internal energy of the phase.
You can only remove so much heat this way, and the rate of heat removal decreases as the room's relative humidity approaches 100%. If you want to use that for constant heating, you will need some way to remove the moist air and replace it with dry air (one that doesn't involve a dehumidifier that puts heat back into the room).
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
$endgroup$
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
3
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
1
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
add a comment |
$begingroup$
One this size is more of a personal cooler, placed right in front of you it will probably keep you a little cooler, it will do little to nothing to cool a normal sized room. But the principle is sound, as water evaporates it becomes cooler than the liquid water. Adding ice will cool the water, so the water vapor will be even cooler. Growing up in the 1960s, in Texas, all we had to cool our house were evaporative coolers (also called water coolers, or swamp coolers), These were large and blew a lot of air with a "squirrel cage" blower inside a box with vented padding on 3 sides which had water pumped over them. They were placed outside of a window so the humidified, cooler air was forced into the room. They would usually keep a large area comfortable even in the middle of summer(usually 20 to 30 degrees F, or more, cooler than the outside temperature). These work best in "dry heat" where humidity is low, as water can evaporate faster. They do not cool as well on rainy days or other times of high humidity.
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
$endgroup$
add a comment |
$begingroup$
It's an evaporative cooler: You fill it with water, it blows the room's air across the water, and the energy required for evaporation is heat that is thus removed from the room.
I don't know how well a small one like that will work, and in any case it is only going to work if the air is fairly dry; but in principle, at least, it is plausible and not a scam.
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
$endgroup$
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
add a comment |
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3 Answers
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3 Answers
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active
oldest
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active
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active
oldest
votes
$begingroup$
I doubt that it even has a cooling element, i suspect that it is just a fan + humidifier.
The fan+humidifier is the cooling element for this unit. It uses purely evaporative cooling to reduce the temperature of the system. It can do this because the phase change between liquid and vapour requires energy. By just passing a convective current of relatively dry air over a liquid water reservoir, heat is taken from the air to evaporate the water. This results in the humidified air being a lower temperature than before it entered the humidifier.
In this case, the heat doesn't just vanish. The heat lost is stored in the latent heat of vaporization of the water. If the vapour in the room were to begin condensation, the heat in the room would start to increase.
Basically, you're just using the humidity as a sort of thermal battery. You're able to store some of the heat in the room in the form of increased relative humidity, instead of having it go towards increasing temperature directly. The energy doesn't leave the system; it's just taken a different form as internal energy of the phase.
You can only remove so much heat this way, and the rate of heat removal decreases as the room's relative humidity approaches 100%. If you want to use that for constant heating, you will need some way to remove the moist air and replace it with dry air (one that doesn't involve a dehumidifier that puts heat back into the room).
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
$endgroup$
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
3
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
1
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
add a comment |
$begingroup$
I doubt that it even has a cooling element, i suspect that it is just a fan + humidifier.
The fan+humidifier is the cooling element for this unit. It uses purely evaporative cooling to reduce the temperature of the system. It can do this because the phase change between liquid and vapour requires energy. By just passing a convective current of relatively dry air over a liquid water reservoir, heat is taken from the air to evaporate the water. This results in the humidified air being a lower temperature than before it entered the humidifier.
In this case, the heat doesn't just vanish. The heat lost is stored in the latent heat of vaporization of the water. If the vapour in the room were to begin condensation, the heat in the room would start to increase.
Basically, you're just using the humidity as a sort of thermal battery. You're able to store some of the heat in the room in the form of increased relative humidity, instead of having it go towards increasing temperature directly. The energy doesn't leave the system; it's just taken a different form as internal energy of the phase.
You can only remove so much heat this way, and the rate of heat removal decreases as the room's relative humidity approaches 100%. If you want to use that for constant heating, you will need some way to remove the moist air and replace it with dry air (one that doesn't involve a dehumidifier that puts heat back into the room).
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
$endgroup$
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
3
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
1
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
add a comment |
$begingroup$
I doubt that it even has a cooling element, i suspect that it is just a fan + humidifier.
The fan+humidifier is the cooling element for this unit. It uses purely evaporative cooling to reduce the temperature of the system. It can do this because the phase change between liquid and vapour requires energy. By just passing a convective current of relatively dry air over a liquid water reservoir, heat is taken from the air to evaporate the water. This results in the humidified air being a lower temperature than before it entered the humidifier.
In this case, the heat doesn't just vanish. The heat lost is stored in the latent heat of vaporization of the water. If the vapour in the room were to begin condensation, the heat in the room would start to increase.
Basically, you're just using the humidity as a sort of thermal battery. You're able to store some of the heat in the room in the form of increased relative humidity, instead of having it go towards increasing temperature directly. The energy doesn't leave the system; it's just taken a different form as internal energy of the phase.
You can only remove so much heat this way, and the rate of heat removal decreases as the room's relative humidity approaches 100%. If you want to use that for constant heating, you will need some way to remove the moist air and replace it with dry air (one that doesn't involve a dehumidifier that puts heat back into the room).
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
$endgroup$
I doubt that it even has a cooling element, i suspect that it is just a fan + humidifier.
The fan+humidifier is the cooling element for this unit. It uses purely evaporative cooling to reduce the temperature of the system. It can do this because the phase change between liquid and vapour requires energy. By just passing a convective current of relatively dry air over a liquid water reservoir, heat is taken from the air to evaporate the water. This results in the humidified air being a lower temperature than before it entered the humidifier.
In this case, the heat doesn't just vanish. The heat lost is stored in the latent heat of vaporization of the water. If the vapour in the room were to begin condensation, the heat in the room would start to increase.
Basically, you're just using the humidity as a sort of thermal battery. You're able to store some of the heat in the room in the form of increased relative humidity, instead of having it go towards increasing temperature directly. The energy doesn't leave the system; it's just taken a different form as internal energy of the phase.
You can only remove so much heat this way, and the rate of heat removal decreases as the room's relative humidity approaches 100%. If you want to use that for constant heating, you will need some way to remove the moist air and replace it with dry air (one that doesn't involve a dehumidifier that puts heat back into the room).
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
answered 8 hours ago
JMacJMac
10.4k2 gold badges23 silver badges38 bronze badges
10.4k2 gold badges23 silver badges38 bronze badges
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
3
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
1
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
add a comment |
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
3
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
1
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
3
3
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
$begingroup$
@SinOfficial "Average" humidity varies a lot with location.
$endgroup$
– JMac
7 hours ago
1
1
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
Note: The evaporative cooler does exactly the same thing as human skin does by sweating, evaporating water to get rid of heat. Thus, increasing the humidity of the air in a room will reduce the ability of the body to cool itself down via transpiration. Now, the body's method is quite a bit more efficient in removing heat from the body itself, it does not need to reduce the heat of the air at all. Thus, I'd much rather just put up a fan and trust my own body to evaporate as much water as it sees fit.
$endgroup$
– cmaster
5 hours ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
$begingroup$
@SinOfficial, in a location like Arizona, where the average humidity is in the single digits, it's incredibly effective at cooling. In a location like Florida, where the average humidity is 100%, it has no effect.
$endgroup$
– Mark
29 mins ago
add a comment |
$begingroup$
One this size is more of a personal cooler, placed right in front of you it will probably keep you a little cooler, it will do little to nothing to cool a normal sized room. But the principle is sound, as water evaporates it becomes cooler than the liquid water. Adding ice will cool the water, so the water vapor will be even cooler. Growing up in the 1960s, in Texas, all we had to cool our house were evaporative coolers (also called water coolers, or swamp coolers), These were large and blew a lot of air with a "squirrel cage" blower inside a box with vented padding on 3 sides which had water pumped over them. They were placed outside of a window so the humidified, cooler air was forced into the room. They would usually keep a large area comfortable even in the middle of summer(usually 20 to 30 degrees F, or more, cooler than the outside temperature). These work best in "dry heat" where humidity is low, as water can evaporate faster. They do not cool as well on rainy days or other times of high humidity.
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
$endgroup$
add a comment |
$begingroup$
One this size is more of a personal cooler, placed right in front of you it will probably keep you a little cooler, it will do little to nothing to cool a normal sized room. But the principle is sound, as water evaporates it becomes cooler than the liquid water. Adding ice will cool the water, so the water vapor will be even cooler. Growing up in the 1960s, in Texas, all we had to cool our house were evaporative coolers (also called water coolers, or swamp coolers), These were large and blew a lot of air with a "squirrel cage" blower inside a box with vented padding on 3 sides which had water pumped over them. They were placed outside of a window so the humidified, cooler air was forced into the room. They would usually keep a large area comfortable even in the middle of summer(usually 20 to 30 degrees F, or more, cooler than the outside temperature). These work best in "dry heat" where humidity is low, as water can evaporate faster. They do not cool as well on rainy days or other times of high humidity.
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
$endgroup$
add a comment |
$begingroup$
One this size is more of a personal cooler, placed right in front of you it will probably keep you a little cooler, it will do little to nothing to cool a normal sized room. But the principle is sound, as water evaporates it becomes cooler than the liquid water. Adding ice will cool the water, so the water vapor will be even cooler. Growing up in the 1960s, in Texas, all we had to cool our house were evaporative coolers (also called water coolers, or swamp coolers), These were large and blew a lot of air with a "squirrel cage" blower inside a box with vented padding on 3 sides which had water pumped over them. They were placed outside of a window so the humidified, cooler air was forced into the room. They would usually keep a large area comfortable even in the middle of summer(usually 20 to 30 degrees F, or more, cooler than the outside temperature). These work best in "dry heat" where humidity is low, as water can evaporate faster. They do not cool as well on rainy days or other times of high humidity.
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
$endgroup$
One this size is more of a personal cooler, placed right in front of you it will probably keep you a little cooler, it will do little to nothing to cool a normal sized room. But the principle is sound, as water evaporates it becomes cooler than the liquid water. Adding ice will cool the water, so the water vapor will be even cooler. Growing up in the 1960s, in Texas, all we had to cool our house were evaporative coolers (also called water coolers, or swamp coolers), These were large and blew a lot of air with a "squirrel cage" blower inside a box with vented padding on 3 sides which had water pumped over them. They were placed outside of a window so the humidified, cooler air was forced into the room. They would usually keep a large area comfortable even in the middle of summer(usually 20 to 30 degrees F, or more, cooler than the outside temperature). These work best in "dry heat" where humidity is low, as water can evaporate faster. They do not cool as well on rainy days or other times of high humidity.
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
answered 6 hours ago
Adrian HowardAdrian Howard
6851 silver badge9 bronze badges
6851 silver badge9 bronze badges
add a comment |
add a comment |
$begingroup$
It's an evaporative cooler: You fill it with water, it blows the room's air across the water, and the energy required for evaporation is heat that is thus removed from the room.
I don't know how well a small one like that will work, and in any case it is only going to work if the air is fairly dry; but in principle, at least, it is plausible and not a scam.
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
$endgroup$
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
add a comment |
$begingroup$
It's an evaporative cooler: You fill it with water, it blows the room's air across the water, and the energy required for evaporation is heat that is thus removed from the room.
I don't know how well a small one like that will work, and in any case it is only going to work if the air is fairly dry; but in principle, at least, it is plausible and not a scam.
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
$endgroup$
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
add a comment |
$begingroup$
It's an evaporative cooler: You fill it with water, it blows the room's air across the water, and the energy required for evaporation is heat that is thus removed from the room.
I don't know how well a small one like that will work, and in any case it is only going to work if the air is fairly dry; but in principle, at least, it is plausible and not a scam.
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
$endgroup$
It's an evaporative cooler: You fill it with water, it blows the room's air across the water, and the energy required for evaporation is heat that is thus removed from the room.
I don't know how well a small one like that will work, and in any case it is only going to work if the air is fairly dry; but in principle, at least, it is plausible and not a scam.
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
answered 8 hours ago
FlytoFlyto
4884 silver badges7 bronze badges
4884 silver badges7 bronze badges
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
add a comment |
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
2
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial The achievable output temperature is called the wet-bulb temperature (en.wikipedia.org/wiki/Wet-bulb_temperature). Which is actually the most interesting measurement of heat with respect to the human body: It is the limit to which your skin can cool itself down via transpiration. Nice values are somewhere between 10°C and 20°C, horribly humid values are somewhere between 20°C and 30°C and positively dangerous values are between 30°C and 35°C. Anything above that is plain deadly. I'd say, as long as you can have fun on your bike, your evaporative cooler achieves <20°C.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
$begingroup$
@SinOfficial Reading the wikipedia article more closely, it seems that wet-bulb temperatures over 30°C are very rare and are only reached in exceptional heat-waves. So, I guess it starts getting dangerous at significantly lower wet-bulb temperatures.
$endgroup$
– cmaster
4 hours ago
add a comment |
SinOfficial is a new contributor. Be nice, and check out our Code of Conduct.
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$begingroup$
I saw a web based advert for something like this. It was pointed out to me and my immediate comment was the thermal energy pumped must go somewhere. Normally it is sent outside. I then figured this must just be a fan that blows air over ice or dry ice or something. The actual refrigeration may not be done by this unit.
$endgroup$
– Lawrence B. Crowell
9 hours ago
5
$begingroup$
Looks like a toy, but a larger-sized version of the same thing sometimes is known as a swamp cooler They work well in dry climates: It takes energy to make water evaporate. Water exposed to dry air will evaporate, and the vapor and the water will become cooler than the ambient air as a result. en.wikipedia.org/wiki/Enthalpy_of_vaporization
$endgroup$
– Solomon Slow
9 hours ago
1
$begingroup$
Having lived with swamp coolers as my primary cooling system for a number of years, I can attest that (A) thy work very well in dry places like southern New Mexico and (B) on the few humid days a year you either suffer or retreat to a place that has refrigerated air.
$endgroup$
– dmckee♦
9 hours ago
$begingroup$
And how much degrees could a room with average humidity and 30°C be cooled down with this technique?
$endgroup$
– SinOfficial
8 hours ago
2
$begingroup$
Starting from, say, 40 C and 10% RH (a nice summer day in the area where I lived with these thing) you'd get about 15 C cooling. Performance drops rapidly with increasing humidity and slowly with decreasing exterior temperature. But beware that a unit sized for a small building is an appreciable fraction of a cubic meter in size and the fan makes a lot of noise. Even in the places where they work well these things are understood to be a cheaper alternative to a real refrigeration unit: something you use if you can't afford the better option.
$endgroup$
– dmckee♦
7 hours ago