大連車載空調由壓縮機(ji)、冷(leng)凝(ning)器(qi)(qi)、節流元件、蒸發(fa)器(qi)(qi)、風機(ji)及必要的(de)(de)控制(zhi)部件構成，用(yong)(yong)于調(diao)(diao)節車(che)內(nei)(nei)溫(wen)度(du)(du)(du)(du)、濕度(du)(du)(du)(du)，給乘員提供舒適(shi)環(huan)(huan)(huan)境的(de)(de)空(kong)(kong)(kong)(kong)調(diao)(diao)系(xi)統(tong)。當(dang)(dang)壓縮機(ji)工作時(shi)，壓縮機(ji)吸入(ru)從蒸發(fa)器(qi)(qi)出(chu)來(lai)的(de)(de)低(di)(di)(di)溫(wen)低(di)(di)(di)壓的(de)(de)氣(qi)(qi)(qi)態(tai)制(zhi)冷(leng)劑(ji)，經壓縮，制(zhi)冷(leng)劑(ji)的(de)(de)溫(wen)度(du)(du)(du)(du)和(he)(he)壓力升高(gao)(gao)(gao)，并(bing)被送入(ru)冷(leng)凝(ning)器(qi)(qi)。在(zai)冷(leng)凝(ning)器(qi)(qi)內(nei)(nei)，高(gao)(gao)(gao)溫(wen)高(gao)(gao)(gao)壓的(de)(de)氣(qi)(qi)(qi)態(tai)制(zhi)冷(leng)劑(ji)把(ba)(ba)熱(re)量(liang)(liang)(liang)傳遞給經過冷(leng)凝(ning)器(qi)(qi)的(de)(de)車(che)外(wai)(wai)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)而液(ye)化，變成液(ye)體。液(ye)態(tai)制(zhi)冷(leng)劑(ji)流經節流裝置時(shi)，溫(wen)度(du)(du)(du)(du)和(he)(he)壓力降(jiang)低(di)(di)(di)，并(bing)進(jin)(jin)入(ru)蒸發(fa)器(qi)(qi)。在(zai)蒸發(fa)器(qi)(qi)內(nei)(nei)，低(di)(di)(di)溫(wen)低(di)(di)(di)壓的(de)(de)液(ye)態(tai)制(zhi)冷(leng)劑(ji)吸收經過蒸發(fa)器(qi)(qi)的(de)(de)車(che)內(nei)(nei)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)的(de)(de)熱(re)量(liang)(liang)(liang)而蒸發(fa)，變成氣(qi)(qi)(qi)體。氣(qi)(qi)(qi)體又被壓縮機(ji)吸入(ru)進(jin)(jin)行下(xia)一輪循環(huan)(huan)(huan)。這(zhe)樣，通過制(zhi)冷(leng)劑(ji)在(zai)系(xi)統(tong)內(nei)(nei)的(de)(de)循環(huan)(huan)(huan)，不斷(duan)吸收車(che)內(nei)(nei)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)的(de)(de)熱(re)量(liang)(liang)(liang)并(bing)排(pai)到車(che)外(wai)(wai)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)中(zhong)，使(shi)(shi)車(che)內(nei)(nei)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)的(de)(de)溫(wen)度(du)(du)(du)(du)逐漸下(xia)降(jiang)。內(nei)(nei)循環(huan)(huan)(huan)可(ke)以(yi)提高(gao)(gao)(gao)空(kong)(kong)(kong)(kong)調(diao)(diao)效(xiao)果，相當(dang)(dang)于把(ba)(ba)室內(nei)(nei)冷(leng)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)再(zai)制(zhi)冷(leng)，空(kong)(kong)(kong)(kong)調(diao)(diao)效(xiao)果當(dang)(dang)然更好了。不過長時(shi)間使(shi)(shi)用(yong)(yong)內(nei)(nei)循環(huan)(huan)(huan)會(hui)(hui)使(shi)(shi)車(che)內(nei)(nei)的(de)(de)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)質(zhi)(zhi)(zhi)量(liang)(liang)(liang)降(jiang)低(di)(di)(di)，可(ke)能讓(rang)人感(gan)覺頭昏腦漲。應當(dang)(dang)開(kai)一會(hui)(hui)兒(er)內(nei)(nei)循環(huan)(huan)(huan)就使(shi)(shi)用(yong)(yong)幾分鐘外(wai)(wai)循環(huan)(huan)(huan)，讓(rang)新(xin)鮮(xian)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)進(jin)(jin)入(ru)車(che)內(nei)(nei)，改善空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)質(zhi)(zhi)(zhi)量(liang)(liang)(liang)。如(ru)果空(kong)(kong)(kong)(kong)調(diao)(diao)內(nei)(nei)外(wai)(wai)循環(huan)(huan)(huan)開(kai)關是(shi)機(ji)械式的(de)(de)撥(bo)桿而非(fei)按鈕，可(ke)以(yi)把(ba)(ba)撥(bo)桿放在(zai)內(nei)(nei)外(wai)(wai)循環(huan)(huan)(huan)的(de)(de)中(zhong)間，讓(rang)車(che)外(wai)(wai)空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)適(shi)量(liang)(liang)(liang)進(jin)(jin)入(ru)，既(ji)能提升空(kong)(kong)(kong)(kong)氣(qi)(qi)(qi)質(zhi)(zhi)(zhi)量(liang)(liang)(liang)，又能提高(gao)(gao)(gao)空(kong)(kong)(kong)(kong)調(diao)(diao)效(xiao)果。此外(wai)(wai)，在(zai)使(shi)(shi)用(yong)(yong)空(kong)(kong)(kong)(kong)調(diao)(diao)除霜除霧時(shi)，要使(shi)(shi)用(yong)(yong)外(wai)(wai)循環(huan)(huan)(huan)才(cai)有效(xiao)。