國標已經規定電熱水器必須安裝漏電保護裝置。國內品牌大部分采用的是防電墻技術，合資品牌主要采用三極斷開技術。
防電墻技術的工作原理是：通過增加電阻，減低漏電的電壓（12V），從而不會發生安全事故；
三極斷開技術采用敏感電子元件，一旦發生意外漏電，迅速（0.1秒）切斷地線、火線和零線，從而起到保護的效果；
出(chu)水(shui)斷電(dian)技術是在出(chu)水(shui)時，自動(dong)(dong)切斷電(dian)源(yuan)。原理是在進水(shui)口加一(yi)個感應水(shui)流的裝置(zhi)，可以是流量(liang)開關、干(gan)簧管、旋流磁片等，當檢(jian)測到(dao)有(you)水(shui)流動(dong)(dong)時，感應裝置(zhi)給出(chu)信號(hao)，控制器(qi)自動(dong)(dong)切斷電(dian)源(yuan)，保(bao)證無電(dian)使用狀態。
電熱(re)(re)水器(qi)在加(jia)熱(re)(re)過程(cheng)會(hui)(hui)形(xing)成(cheng)水垢(gou)，一旦水垢(gou)依附(fu)在發熱(re)(re)管(guan)(guan)(guan)上(shang)或者內膽上(shang)對(dui)電熱(re)(re)水器(qi)的性能(neng)都會(hui)(hui)大(da)打折扣。如(ru)果依附(fu)在發熱(re)(re)管(guan)(guan)(guan)上(shang)，加(jia)熱(re)(re)效率降低，甚(shen)至出現爆管(guan)(guan)(guan)；依附(fu)在內膽上(shang)，由于內膽受熱(re)(re)不(bu)均，也會(hui)(hui)導致內膽破裂。鎂棒(bang)(bang)可(ke)以防止結水垢(gou)保護內膽、發熱(re)(re)管(guan)(guan)(guan)。鎂棒(bang)(bang)在溶解水垢(gou)時(shi)形(xing)成(cheng)鎂鹽，從而損(sun)耗鎂棒(bang)(bang)，一般而言最長每隔2年就要更換鎂棒(bang)(bang)，不(bu)然(ran)一旦鎂棒(bang)(bang)消耗完，電熱(re)(re)就會(hui)(hui)形(xing)成(cheng)很多水垢(gou)影響機子的使用壽命，并且不(bu)安全。
是(shi)的(de)，接(jie)地安全(quan)是(shi)電(dian)熱(re)(re)水器(qi)(qi)安裝(zhuang)的(de)基本條件(jian)，家中電(dian)路(lu)接(jie)地(地線)沒(mei)有安全(quan)保證時(shi)不要(yao)(yao)選擇電(dian)熱(re)(re)水器(qi)(qi)。購買后請嚴格按照使用說明書中的(de)要(yao)(yao)求進行安裝(zhuang)和使用，安裝(zhuang)的(de)時(shi)候，電(dian)熱(re)(re)水器(qi)(qi)的(de)接(jie)地裝(zhuang)置很重要(yao)(yao)，如果(guo)沒(mei)有接(jie)地線，電(dian)熱(re)(re)水器(qi)(qi)容易漏(lou)電(dian)，電(dian)源插頭(tou)上的(de)“漏(lou)電(dian)保護”裝(zhuang)置也(ye)會形同虛設，所以(yi)安裝(zhuang)前一定(ding)要(yao)(yao)檢查插座是(shi)否有接(jie)地線。
一般40L的電(dian)(dian)熱(re)(re)(re)水(shui)器(qi)(qi)(qi)在1500W功(gong)(gong)(gong)率(lv)加熱(re)(re)(re)到最高溫度(du)，時(shi)間大約(yue)在50~60分鐘。2000W功(gong)(gong)(gong)率(lv)的情況下一般需要35~45分鐘。速(su)熱(re)(re)(re)電(dian)(dian)熱(re)(re)(re)水(shui)器(qi)(qi)(qi)20L在4000W功(gong)(gong)(gong)率(lv)下加熱(re)(re)(re)時(shi)間約(yue)為16分鐘，根據加熱(re)(re)(re)時(shi)間也可以判斷電(dian)(dian)熱(re)(re)(re)水(shui)器(qi)(qi)(qi)的性能功(gong)(gong)(gong)率(lv)是(shi)否(fou)正常。
安(an)(an)(an)(an)全閥(fa)(fa)(fa)起(qi)單向(xiang)進水(shui)(shui)(shui)和超壓(ya)(ya)(ya)安(an)(an)(an)(an)全保護的作(zuo)用。在自(zi)來水(shui)(shui)(shui)壓(ya)(ya)(ya)力突然增高(gao)或加(jia)熱(re)(re)過(guo)熱(re)(re)而造成內膽(dan)承(cheng)壓(ya)(ya)(ya)過(guo)大時(shi)(shi)，安(an)(an)(an)(an)全閥(fa)(fa)(fa)就會自(zi)動滴(di)(di)漏(lou)泄(xie)壓(ya)(ya)(ya)，不(bu)至于因壓(ya)(ya)(ya)力過(guo)高(gao)而損壞內膽(dan)。所(suo)以說(shuo)在加(jia)熱(re)(re)過(guo)程中，安(an)(an)(an)(an)全閥(fa)(fa)(fa)緩慢滴(di)(di)水(shui)(shui)(shui)是(shi)正常正象(xiang)(xiang)，并不(bu)是(shi)熱(re)(re)水(shui)(shui)(shui)器質量(liang)問題。這(zhe)也(ye)提醒用戶使(shi)用熱(re)(re)水(shui)(shui)(shui)器時(shi)(shi)，進水(shui)(shui)(shui)壓(ya)(ya)(ya)力不(bu)能太高(gao)，以免造成安(an)(an)(an)(an)全閥(fa)(fa)(fa)滴(di)(di)水(shui)(shui)(shui)嚴重。處理方法(fa)：關閉進水(shui)(shui)(shui)閥(fa)(fa)(fa)，把(ba)混(hun)水(shui)(shui)(shui)閥(fa)(fa)(fa)旋鈕(niu)調到高(gao)溫處打開即(ji)可避免單向(xiang)安(an)(an)(an)(an)全閥(fa)(fa)(fa)的漏(lou)水(shui)(shui)(shui)現象(xiang)(xiang)，使(shi)水(shui)(shui)(shui)從花(hua)灑(sa)中滴(di)(di)出；如(ru)果未安(an)(an)(an)(an)裝混(hun)水(shui)(shui)(shui)閥(fa)(fa)(fa)，可把(ba)出熱(re)(re)水(shui)(shui)(shui)閥(fa)(fa)(fa)打開一(yi)點，進行(xing)泄(xie)壓(ya)(ya)(ya)，這(zhe)樣也(ye)可避免單向(xiang)安(an)(an)(an)(an)全閥(fa)(fa)(fa)的漏(lou)水(shui)(shui)(shui)現象(xiang)(xiang)。最后如(ru)無法(fa)控制安(an)(an)(an)(an)全閥(fa)(fa)(fa)滴(di)(di)水(shui)(shui)(shui)現象(xiang)(xiang)，建議在安(an)(an)(an)(an)全閥(fa)(fa)(fa)前加(jia)裝一(yi)個減壓(ya)(ya)(ya)閥(fa)(fa)(fa)。
電熱水(shui)(shui)器(qi)(qi)內膽(dan)總是(shi)裝(zhuang)滿(man)水(shui)(shui)的并有一定壓力。當(dang)通電加(jia)(jia)(jia)熱到(dao)(dao)設(she)定的溫(wen)度(du)時，溫(wen)控(kong)(kong)器(qi)(qi)切(qie)斷(duan)供應加(jia)(jia)(jia)熱管的電源。當(dang)熱水(shui)(shui)流(liu)出(chu)后，冷(leng)水(shui)(shui)進入內膽(dan)，溫(wen)控(kong)(kong)器(qi)(qi)的溫(wen)度(du)傳感器(qi)(qi)被冷(leng)水(shui)(shui)冷(leng)卻(que)，溫(wen)控(kong)(kong)器(qi)(qi)接通加(jia)(jia)(jia)熱管的電源，加(jia)(jia)(jia)熱管工作。冷(leng)水(shui)(shui)被加(jia)(jia)(jia)熱直至(zhi)達到(dao)(dao)設(she)定溫(wen)度(du)。內膽(dan)里的所(suo)有水(shui)(shui)保持這(zhe)一溫(wen)度(du)，直到(dao)(dao)熱水(shui)(shui)被放出(chu)。
（1）一般在使用一段時間后發熱管絕緣性能會出現下降現象，測量時絕緣電阻值不穩定，當漏電電流超過一定數值時，漏電保護器插頭就會立即智能處理：檢
查排除原因，必要時更換發熱管。
（2）當漏電保護插頭與插座接觸不良時，產生的電火花致使溫度過高，使溫敏器開關產生錯誤智能處理：更換插座。
（3）當漏電保護插頭與超溫保護器出現故障時：檢查更換超溫保護器或漏電保護插頭。
（4）當任何帶電元器件與機殼之間產生漏電時，都會產生熱水器正常加熱工作狀態下突然跳閘：檢查漏電原因排除更換元器件。
主(zhu)要原因是(shi)(shi)：電(dian)(dian)(dian)(dian)(dian)源(yuan)插(cha)座(zuo)無(wu)電(dian)(dian)(dian)(dian)(dian)或接(jie)觸不良；溫控器(qi)失靈或發熱管及其他部位有(you)(you)(you)漏(lou)電(dian)(dian)(dian)(dian)(dian)；處理方法：先用電(dian)(dian)(dian)(dian)(dian)筆檢(jian)查(cha)電(dian)(dian)(dian)(dian)(dian)源(yuan)插(cha)座(zuo)是(shi)(shi)否(fou)(fou)有(you)(you)(you)電(dian)(dian)(dian)(dian)(dian)以及漏(lou)電(dian)(dian)(dian)(dian)(dian)保護(hu)插(cha)頭(tou)與插(cha)座(zuo)的接(jie)觸是(shi)(shi)否(fou)(fou)良好，再按下漏(lou)電(dian)(dian)(dian)(dian)(dian)保護(hu)插(cha)頭(tou)的復(fu)位按鈕，即可恢復(fu)正常。如不能復(fu)位的，肯定有(you)(you)(you)漏(lou)電(dian)(dian)(dian)(dian)(dian)現象(xiang)，用電(dian)(dian)(dian)(dian)(dian)筆檢(jian)查(cha)是(shi)(shi)否(fou)(fou)漏(lou)電(dian)(dian)(dian)(dian)(dian)，如漏(lou)電(dian)(dian)(dian)(dian)(dian)用電(dian)(dian)(dian)(dian)(dian)筆查(cha)明漏(lou)電(dian)(dian)(dian)(dian)(dian)部位，設法消除(chu)漏(lou)電(dian)(dian)(dian)(dian)(dian)；可檢(jian)查(cha)溫控器(qi)是(shi)(shi)否(fou)(fou)失靈，電(dian)(dian)(dian)(dian)(dian)熱管是(shi)(shi)否(fou)(fou)損壞。
接地(di)異常是指(zhi)用(yong)戶(hu)電源插座(zuo)中電源相位存在(zai)著(zhu)嚴重問(wen)題，如缺地(di)線(xian)、零火線(xian)調反(fan)、地(di)線(xian)帶電等(deng)可能性。雖然電熱(re)水(shui)器(qi)能正常加熱(re)使用(yong)，但實際中存在(zai)嚴重的安(an)全危害(hai)。要求(qiu)用(yong)戶(hu)安(an)排專(zhuan)業電工對自身的用(yong)電情況進行檢查(cha)和維(wei)修，以排除用(yong)電危害(hai)。
發熱(re)管(guan)插頭與電源(yuan)線(xian)連接部(bu)位接觸(chu)不良(liang)或(huo)(huo)斷線(xian)：檢(jian)查(cha)發熱(re)管(guan)是否(fou)已壞，檢(jian)查(cha)電源(yuan)連接線(xian)是否(fou)良(liang)好：更換(huan)(huan)發熱(re)管(guan)、或(huo)(huo)更換(huan)(huan)連接線(xian)。
溫控(kong)器連接部位接觸不良或斷線、指示燈已(yi)壞：檢(jian)查溫控(kong)器及指示燈排除(chu)更換(huan)元件。溫控(kong)器燒(shao)斷：更換(huan)溫控(kong)器.
