Network spread minimum working temperature 7 ℃ "air conditioning" is that true?
These two days, two claims about air conditioning heat transfer on the Internet, "air conditioning minimum working temperature is 7 ℃", "12 ℃ below zero, may not have air conditioning heating effect", also included a few brand air conditioning minimum working temperature survey, make a lot of people off guard. Is that really so? If air conditioning can't work at such a low temperature, then the air conditioning in the cold region of the north is just a decoration?
Yesterday, the reporter consulted several air conditioning professionals on this question, the answer is: basically, this is true.
Oaks air conditioning customer service staff.
General family expenses air conditioning, the - 5 ℃ or so, outside air conditioning machine will frost, air conditioning start preheating time will increase greatly. The - 7 ℃, air conditioning heating effect will sell at a discount greatly, with lower temperature, air conditioning may have no heating effect.
Gree air conditioning hangzhou staff.
Summer outdoor 38 ℃, 28 ℃ indoor, indoor is very cool, only sent 10 ℃. But in winter, outdoor - 8 ℃, 28 ℃, you become the middle to 30 ℃. Moreover, the humidity in jiangnan area is large, and the air conditioner is easy to freeze.
Such as the winter of 2008, hangzhou temperature is low, some air conditioning machine blade icing on the outside, you may give in addition to the outside can see ice, but there still have ice, one to start, even the blade out."
"When installing an outdoor unit, it is better to have a sunny face, to be more prone to ice frosting on the surface, and not on the roof. In the following weather, it is advisable to use a home heater. The sun is good.
(the staff member also reminded that "H1" appears on the remote control of the air conditioner, which is the automatic defrosting of the air conditioner, so you don't have to worry about it.)
Why is the temperature too low for air-conditioning?
The detailed principle is very complicated, said an engineer in the after-sales service department of hisense air conditioning. Simply put, the air conditioning is mainly a process of air convection. The air inside is out and the air outside is inside. How to let air conditioning blow out cold air and hot air? Compressor and refrigerant (such as freon) are mainly used on air conditioner. The effect of the compressor on the refrigerant, the refrigerant becomes high temperature or high pressure or low temperature, resulting in cold or hot air.
"Compressor is to rotate, the working temperature range, just like the car engine, if the ambient temperature is too low, can affect the rotation of the compressor, is lack of power, influence to the compressed air, thus affect the heating."
Cold air conditioning does not heat the air conditioning is not bad, the air conditioning unit is still diligent in the work, only, for a long period of time, it is in the condenser defrost.
"Often have such a situation, indoor machine not out of the wind, the SOB, outdoor this time is in the defrosting, also is not to say that at a certain temperature, the air conditioner doesn't work right away, but the effect will be greatly decreased. General air conditioning that decide frequency of work, for example, limit is 7 ℃, frequency conversion air conditioning work is limit - 10 ℃, the - 8 ℃ or - 11 ℃, air conditioning can still work, but the probability of defrosting and time will be greatly extended, defrosting was 20 minutes, 40 minutes warm wind, now turned into a 40 minutes to defrost, 20 minutes warm wind, can guarantee the indoor air temperature?"
The industry authority, professor Chen guangming, a professor of refrigeration and cryogenic engineering at zhejiang university, confirmed the theory, and he talked about a third reason.
"Air conditioning refrigerant, with the loss of the environmental temperature, the density will be more and more small, by the amount of the compressor is less and less, the second law of thermodynamics has proved, it's just like with a water pump water, climbing the skyer water more difficult, refrigerant, less air conditioning effect is not obvious. In the market, no matter the old and new air conditioner, 95% is the compressor, although there is a small part of the central air conditioning may not be used by the compressor, but it is affected by the ambient temperature.
Is it possible that the air conditioning will not be used in the winter in the north?
Chance to defrost the hisense engineer said, basically see the local temperature and humidity and time, "the north also can open air conditioning, but air dry in north China, the south is different, the main is too wet, defrosting is sure more frequently."
Is the frequency conversion air conditioning not afraid of cold?
Professor Chen gm said, frequency conversion air conditioning is mainly the speed of the compressor can change, more or less, in the case of low temperature, strengthening the speed to pass more refrigerants, but relatively speaking, power consumption is also increasing greatly.
There, "the environment temperature and working temperature limitation, there are some different technology now, get some air conditioning - 20 ℃ can also be used, but heating efficiency is low, can only say that can still work."
The air conditioning that has electric heating function, whether the temperature is low also ok?
According to professor Chen guangming, electric heating is not a new technology, it is the most primitive technology.
"It is electricity that is converted into heat. Junior high school physics is not have any, can produce heat current through the resistance, is in the air conditioning Ann resistance, with the small sun, blown by wind resistance heating, actually, is certainly more save electricity by generating hot air compressor.
"From the energy consumption, electric heating actually is the least cost-effective way, related calculation, in low temperature environment, about every 1 ℃ below the 2% increase in power."