Shadowing Practice: Air Conditioning System Basics hvacr how does it work - Learn English Speaking with Video

Ders oluşturuluyor...
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sponsored by danfoss when we look at a typical refrigeration system we have the compressor
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the condenser the expansion valve and the evaporator the condenser
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and the evaporator are both heat exchangers the condenser sits outside the property
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and the evaporator sits inside the room being cooled the compressor circulates a refrigerant in the pipe work
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which cycles between all of these components the expansion valve regulates
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the flow of refrigerant the refrigerant is a specially designed fluid
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which can change between being a liquid and a gas very easily and that's
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because it has a very low boiling point for example refrigerant
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are for 10 a will boil at negative 48 degrees Celsius
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or negative 55 degrees Fahrenheit although this will change with pressure
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but if the refrigerant is inside a pipe within a room
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and the room is at 30 degrees Celsius
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or 86 degrees Fahrenheit then this will be more than enough to cause it to boil from a liquid into a vapor.
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By the way if you want some refrigerant charts you can download these for free from our website.
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I'll link to these in the video description down below.
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So the The refrigerant is entering the evaporator as a low pressure, low temperature liquid vapor mixture.
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It flows on the inside of the pipe
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and at the same time a fan is moving the ambient air of the room over the outside of the pipe.
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This causes the refrigerant to boil.
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It will absorb the heat from the air through the pipe wall and then it evaporates.
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As the refrigerant evaporates, it carries away the heat.
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It's similar to when we boiled water.
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The water heats up, it evaporates and turns into steam and carries this heat away.
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So the air on the outside is entering hot and it's leaving cold.
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The refrigerant continues to travel through the evaporator, picking up more heat which boils it further until it becomes slightly superheated.
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This basically means it's now completely gas and doesn't contain any droplets of liquid refrigerant.
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Liquid damages the compressor, so we want to ensure it can't reach the compressor.
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The compressor sucks in the refrigerant, which is leaving the evaporator as a low -pressure, low -temperature, slightly superheated vapour.
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It then squeezes this together into a much smaller space, and so the pressure increases.
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All the heat which was picked up in the evaporator is now contained in a much smaller volume, so the temperature will increase.
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This is very important and we will see why in just a moment.
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But if you've ever pumped up a bicycle tyre, you will notice the pump becomes hotter as it's compressing the air.
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The refrigerant is then pushed into the condenser where it enters as a high -pressure, high -temperature, superheated vapour.
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the condenser is located outside
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and the outside air might be very warm on a summer's
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day as heat always flows from hot to cold we need to ensure
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that the refrigerant is hotter than the outside air otherwise the
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unwanted heat will not be able to leave the refrigerant and leave our system
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a fan will help to blow ambient air over the condenser to remove this heat
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so the outside air is entering warm picking up heat
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and leaving hot as the heat is removed by the air
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this causes the refrigerant to condense back into a liquid it's a little bit like
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when steam hits the window on a cold day the window is cold
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so it condenses the steam from a vapor into a liquid
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and then this liquid starts to run down the window the
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refrigerant therefore exits as a high pressure medium temperature saturated liquid
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and this heads to the expansion valve the expansion valve needs
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to regulate the amount of refrigerant entering the evaporator to control the superheat
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if it allows too much refrigerant to flow it can flood the evaporator
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so the refrigerant doesn't evaporate a liquid reaches the compressor
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and possibly destroys it but
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if it lets in too little refrigerant the system won't provide enough cooling and
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so it operates inefficiently the expansion valve regulates the refrigerant by
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only allowing it to pass through a small hole this creates
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a large pressure difference across the valve one side is the high -pressure liquid the other side is almost empty
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The small hole causes it to almost spray into the evaporator as a part liquid, part vapor mixture.
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The refrigerant will expand to try and fill the empty space on the other side
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and this will cause it to drop in pressure as well as temperature.
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It's a little bit like spraying a deodorant can or a spray paint can.
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It flows through a small hole causing it to expand as a part vapor
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and part liquid mixture
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and then we can feel the can become cooler now the
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original method to control this was by using a fixed orifice device
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and you might still find these on the back of your
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refrigerators the hole within this device was a fixed size
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so the entire system would simply turn on
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and off to meet the cooling demand it does work
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but we can't maintain a stable temperature control
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because the system is simply turning on
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and off the next evolution was the thermostatic expansion valve this is still widely used today
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and it senses the superheat at the outlet through a bulb
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which is filled with another refrigerant this other refrigerant will expand to close the valve
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when the superheat is too high and it condenses to open the valve when the superheat is too low.
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This type of valve needs to be manually calculated and adjusted by a technician.
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It does work very well but it's prone to mistakes.
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It also takes a long time to calculate and set up
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and it is also only adjusted once per service visit which is not ideal.
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It will also not allow peak performance.
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However it does work very well and these will continue to be used for many years.
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And And so the latest evolution is to use electronic expansion valves.
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These use a controller to measure the exact temperature and pressure
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and adjust the valve position automatically in real time to ensure optimal performance and maximum system efficiency.
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Okay that's it for this video but to continue learning about HVAC
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and refrigeration engineering click on one of the videos on screen now and I'll catch you there for the next lesson.
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Bu dersin kelimeleri ve konuşma notları

Bu konuşma dersi “Air Conditioning System Basics hvacr how does it work” videosuna dayanıyor. En çok tekrarlanan kelimeler: refrigerant, liquid, valve, heat, evaporator. Bu videoda gölgeleme çalışması için 85 cümle ve 1097 kelime var. Konuşma bölümü 7:15 sürüyor. Konuşmacı dakikada yaklaşık 151 kelimeyle, günlük konuşmaya yakın doğal bir hızda konuşuyor. Kelimelerin yalnızca %77’i İngilizcede en sık kullanılan 3.000 kelime arasında, bu yüzden kelime dağarcığı zorlayıcı.

Bu videodaki önemli kelimeler

Videodan öğrenmeye değer 15 kelime, telaffuzu ve anlamıyla:

KelimeTelaffuzAnlam
liquid isim/ˈlɪk.wɪd/sıvı, likit
valve isim/ˈvælv/sibop, supap
boil fiil/bɔɪ(ə)l/kaynatmak
pipe isim/ˈpaɪp/düdük, kaval
vapor isim/ˈveɪpɚ/buhar
mixture isim/ˈmɪkst͡ʃɚ/karıştırmak
spray isim/spɹeɪ/serpinti, çisenti
regulate fiil/ˈɹɛɡ.jə.leɪt/regüle etmek
pump isim/pʌmp/pompa
calculate fiil/ˈkælkjʊleɪt/hesaplamak
stable isim/ˈsteɪ.bəl/ahır
lesson isim/ˈlɛs.ən/ders, çimke
suck fiil/sʌk/emmek
efficiency isim/ɪˈfɪʃ.ən.si/verimlilik
exit isim/ˈɛɡzət/çekilme, çıkış

Duyacağınız deyimsel fiiller

KelimeAnlam
heat up fiilısınmak, ısıtmak

Bu videodaki dil bilgisi

Konuşmacının en çok kullandığı yapılar, videodaki sözcüklerin aynısıyla:

YapıVideoda
Edilgen yapı be + fiilin üçüncü hâli — kimin yaptığı değil, ne olduğu önemlibeing cooled · was picked · is located
İlgi cümlecikleri who / which + cümle — bir kişi ya da şey hakkında ek bilgirefrigerant, which is · heat which was · visit which is

Dikkat edilecek telaffuzlar

Konuşmacı can't, doesn't, I'll gibi kısaltılmış biçimleri 9 kez kullanıyor. Bunları duyduğunuz gibi kısa söyleyin.

  • “sh” ve “zh” sesleri: evolution /ˌiːvəˈluːʃ(ə)n/, efficiency /ɪˈfɪʃ.ən.si/, specially /ˈspɛʃəli/, technician /tɛkˈnɪʃən/
  • Uzun kelimeler — vurguyu doğru yere koyun: evolution /ˌiːvəˈluːʃ(ə)n/, efficiency /ɪˈfɪʃ.ən.si/, manually /ˈmænj(u)əliː/, refrigerator /ɹɪˈfɹɪd͡ʒ.əˌɹeɪ.tɚ/, evaporator /ɪˈvæp.ə.ɹeɪt.ɚ/

Türkçe konuşanların zorlandığı sesler:

  • /w/ — dudaklar yuvarlak, /v/ değil: liquid /ˈlɪk.wɪd/, squeeze /skwiːz/, unwanted /ʌnˈwɒntɪd/
  • Kelime başındaki ünsüz kümesi — araya ünlü eklemeyin: spray /spɹeɪ/, stable /ˈsteɪ.bəl/, flood /flʌd/, fluid /ˈflu.ɪd/, sponsor /ˈspɒn.səː/
  • /æ/ — “e”den daha açık: valve /ˈvælv/, expand /ɪkˈspænd/, calculate /ˈkælkjʊleɪt/, ambient /ˈæm.bi.ənt/, absorb /æbˈsɔɹb/

Bu videoyla nasıl çalışılır

  1. Videonun tamamını konuşmadan bir kez dinleyin ve bilmediğiniz kelimeleri not edin.
  2. 0,75× hızla başlayın, cümle cümle tekrar edin ve kolaylaşınca normal hıza dönün.
  3. Kendinizi kaydedin ve orijinaliyle karşılaştırın; liquid, valve, boil gibi kelimelere özellikle dikkat edin.

Gölgeleme Tekniği Nedir?

Gölgeleme, başlangıçta profesyonel tercüman eğitimi için geliştirilen ve çok dilli Dr. Alexander Arguelles tarafından popüler hale getirilen, bilim destekli bir dil öğrenme tekniğidir. Yöntem basit ama güçlüdür: ana dili İngilizce olan bir sesi dinler ve hemen yüksek sesle tekrar edersiniz — konuşmacıyı 1-2 saniye gecikmeyle takip eden bir gölge gibi. Pasif dinleme veya dilbilgisi alıştırmalarının aksine, gölgeleme beyninizi ve ağız kaslarınızı gerçek konuşma kalıplarını eşzamanlı olarak işlemeye ve yeniden üretmeye zorlar. Araştırmalar, telaffuz doğruluğu, tonlama, ritim, bağlı konuşma, dinleme anlama ve konuşma akıcılığını önemli ölçüde geliştirdiğini göstermektedir — bu da onu IELTS Konuşma hazırlığı ve gerçek dünya İngilizce iletişimi için en etkili yöntemlerden biri yapar.

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