一、充注制冷劑的方法有哪些
制(zhi)冷劑(ji)(ji)是空調(diao)等機器設備(bei)、制(zhi)冷裝備(bei)進行制(zhi)冷操作(zuo)的媒(mei)介物質,如果制(zhi)冷劑(ji)(ji)泄露或不足了,制(zhi)冷效果就會大(da)打折扣(kou),這時候就需要給(gei)裝置重新充注制(zhi)冷劑(ji)(ji),那么制(zhi)冷劑(ji)(ji)怎么充注呢?常見的方法有以下四種:
1、定量充注法
利用專用的制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)定量(liang)充(chong)(chong)注(zhu)器,按要求的制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)型號及注(zhu)入(ru)量(liang)來充(chong)(chong)注(zhu)制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji),將制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)定量(liang)充(chong)(chong)注(zhu)器與制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)循(xun)環(huan)系(xi)(xi)統(tong)連(lian)接好,打開相應的閥門(men),讓(rang)制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)鋼瓶中(zhong)的制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)流(liu)入(ru)量(liang)筒中(zhong);對制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)循(xun)環(huan)系(xi)(xi)統(tong)抽真空(kong)后,打開定重充(chong)(chong)注(zhu)器閥門(men),量(liang)筒中(zhong)的制(zhi)(zhi)(zhi)冷劑(ji)(ji)(ji)便進(jin)入(ru)系(xi)(xi)統(tong)中(zhong)。
2、稱重充注法
將制(zhi)(zhi)冷(leng)(leng)劑鋼(gang)瓶(ping)(ping)傾斜倒放(fang)在小臺(tai)秤的(de)托盤上,通過(guo)干燥過(guo)濾(lv)器、加液管與三(san)通閥(fa)相(xiang)連,連接前先用制(zhi)(zhi)冷(leng)(leng)劑頂出連接管內的(de)空氣(qi),等稱出制(zhi)(zhi)冷(leng)(leng)劑鋼(gang)瓶(ping)(ping)的(de)重量后(hou),再(zai)減(jian)去制(zhi)(zhi)冷(leng)(leng)劑的(de)充注(zhu)量,調好秤砣(tuo)的(de)位置,然后(hou)打(da)開三(san)通閥(fa)和制(zhi)(zhi)冷(leng)(leng)劑鋼(gang)瓶(ping)(ping)的(de)閥(fa)門,使制(zhi)(zhi)冷(leng)(leng)劑緩緩流(liu)入制(zhi)(zhi)冷(leng)(leng)循環系統即可(ke)。當小臺(tai)秤的(de)秤桿上移平衡時,立即關閉三(san)通閥(fa)。
3、表壓充注法
通(tong)(tong)(tong)(tong)過控制制冷劑(ji)(ji)循環系(xi)統(tong)的低(di)壓(ya)(ya)吸氣(qi)壓(ya)(ya)力(li)來決定(ding)充(chong)注量,將正置的制冷劑(ji)(ji)鋼瓶通(tong)(tong)(tong)(tong)過干燥過濾器、接(jie)管與(yu)三(san)(san)通(tong)(tong)(tong)(tong)閥(fa)相接(jie),打開三(san)(san)通(tong)(tong)(tong)(tong)閥(fa)后,制冷劑(ji)(ji)氣(qi)體即(ji)可(ke)利用(yong)真空進入制冷劑(ji)(ji)循環系(xi)統(tong)內(nei);當三(san)(san)通(tong)(tong)(tong)(tong)閥(fa)上真空表(biao)壓(ya)(ya)力(li)值(zhi)升至0.45MPa(空調器應升至0.5-0.6MPa)時,關閉三(san)(san)通(tong)(tong)(tong)(tong)閥(fa),通(tong)(tong)(tong)(tong)電(dian)讓(rang)壓(ya)(ya)縮(suo)機(ji)運(yun)轉,當真空表(biao)壓(ya)(ya)力(li)降為零時,再(zai)打開三(san)(san)通(tong)(tong)(tong)(tong)閥(fa),調整壓(ya)(ya)力(li)為0.02-0.05MPa,再(zai)讓(rang)壓(ya)(ya)縮(suo)機(ji)運(yun)轉一(yi)段(duan)時間,直(zhi)到吸氣(qi)壓(ya)(ya)力(li)穩(wen)定(ding)不變(bian),壓(ya)(ya)力(li)表(biao)的壓(ya)(ya)力(li)值(zhi)達到1.6-2.0MPa時,可(ke)停止充(chong)注制冷劑(ji)(ji)。
4、經驗充注法
充(chong)注制冷(leng)劑(ji)使(shi)真空表壓力為0.2-0.25MPa(空調為0.3-0.4MPa)左右時,關閉三通閥,通電使(shi)壓縮機(ji)運行30min,觀察制冷(leng)系(xi)統的工作(zuo)情(qing)況。若蒸發(fa)器已結滿霜、冷(leng)凝器發(fa)熱、低壓吸(xi)氣管發(fa)涼,則說明(ming)制冷(leng)劑(ji)充(chong)注量合適。經驗法(fa)可配合表壓法(fa)和稱重法(fa)使(shi)用。
二、制冷劑的充注要注意哪些事項
制(zhi)冷(leng)(leng)劑(ji)是制(zhi)冷(leng)(leng)系(xi)統的核心(xin)媒介,制(zhi)冷(leng)(leng)劑(ji)充(chong)注(zhu)是否正(zheng)(zheng)確,關系(xi)到(dao)制(zhi)冷(leng)(leng)系(xi)統的正(zheng)(zheng)常運轉,因此要采用正(zheng)(zheng)確的制(zhi)冷(leng)(leng)劑(ji)充(chong)注(zhu)方法,還(huan)要注(zhu)意一些(xie)事項(xiang)。制(zhi)冷(leng)(leng)劑(ji)充(chong)注(zhu)注(zhu)意事項(xiang)有:
1、制冷劑的量要合適
制(zhi)(zhi)冷(leng)(leng)劑(ji)充(chong)注(zhu)不足(zu)(zu),會(hui)使(shi)蒸(zheng)發器蒸(zheng)發量(liang)不足(zu)(zu),導(dao)致壓(ya)縮機吸氣壓(ya)力過低,冷(leng)(leng)量(liang)減(jian)少并可能(neng)使(shi)壓(ya)縮機過熱;充(chong)注(zhu)過量(liang)又(you)會(hui)使(shi)進(jin)入(ru)冷(leng)(leng)凝器的(de)制(zhi)(zhi)冷(leng)(leng)劑(ji)太多,導(dao)致排氣壓(ya)力過高,液態制(zhi)(zhi)冷(leng)(leng)劑(ji)回流,甚至可能(neng)損壞(huai)壓(ya)縮機。
2、注意制冷劑的形態
制(zhi)(zhi)冷(leng)劑(ji)有(you)氣態和液態兩種,不同(tong)種類的(de)制(zhi)(zhi)冷(leng)劑(ji)充(chong)(chong)注方法也有(you)所(suo)差(cha)異,一般來說,只(zhi)需(xu)少量制(zhi)(zhi)冷(leng)劑(ji)充(chong)(chong)入系統(tong)時(shi),通常使用氣態充(chong)(chong)注法,精度更高;需(xu)要充(chong)(chong)注大量制(zhi)(zhi)冷(leng)劑(ji)則多采用液體充(chong)(chong)注法,速度更快。
3、充注過量如何放出制冷劑
充(chong)注制冷(leng)劑時,有時需要(yao)先將里面的制冷(leng)劑放(fang)出來(lai);充(chong)注過量(liang)時也需要(yao)放(fang)出多余的制冷(leng)劑,如果系統含制冷(leng)劑充(chong)注量(liang)超過3-5kg,是(shi)有回(hui)收價值的,可以用專(zhuan)門(men)的回(hui)收裝置回(hui)收;不然的話,讓制冷(leng)劑以蒸氣(qi)狀(zhuang)排至大氣(qi)中即(ji)可。