正(zheng)壓送(song)(song)風(feng)(feng)一(yi)般(ban)設在樓梯(ti)間(jian)，出現(xian)火(huo)警時著火(huo)層與相鄰(lin)上下層正(zheng)壓送(song)(song)風(feng)(feng)機開啟(qi)，輸送(song)(song)新鮮空氣(qi)并阻(zu)止(zhi)樓梯(ti)間(jian)防火(huo)門(men)開向樓梯(ti)間(jian)----阻(zu)止(zhi)煙(yan)氣(qi)進入樓梯(ti)間(jian)人們逃生時不被煙(yan)氣(qi)搶著。排(pai)煙(yan)風(feng)(feng)機通過排(pai)煙(yan)風(feng)(feng)管、風(feng)(feng)口排(pai)除(chu)煙(yan)氣(qi)。當(dang)煙(yan)氣(qi)溫度高于(yu)280度時自動關(guan)閉(bi)。

正壓(ya)(ya)送風用(yong)于防(fang)(fang)排煙(yan)(yan)樓(lou)梯(ti)(ti)(ti)間(jian)和(he)防(fang)(fang)排煙(yan)(yan)共用(yong)前(qian)(qian)室(shi)，主要(yao)是(shi)保證在著(zhu)火(huo)時，樓(lou)梯(ti)(ti)(ti)間(jian)和(he)前(qian)(qian)室(shi)壓(ya)(ya)力大于走(zou)道和(he)其他公(gong)共區域，保證煙(yan)(yan)氣不進入前(qian)(qian)室(shi)和(he)樓(lou)梯(ti)(ti)(ti)間(jian)的。系統(tong)一般分為(wei)(wei)2種類型，一種是(shi)自垂百葉風口(kou)在屋頂(ding)加(jia)(jia)280度防(fang)(fang)火(huo)閥。另一種是(shi)電動正壓(ya)(ya)送風口(kou)，可分別控制各層的。又名加(jia)(jia)壓(ya)(ya)送風系統(tong)。為(wei)(wei)避免出現超(chao)壓(ya)(ya)情況(kuang)，加(jia)(jia)旁通，進行(xing)泄壓(ya)(ya)。

排(pai)煙(yan)(yan)(yan)系統多用(yong)于地(di)下室，大(da)型商(shang)場，超(chao)大(da)的防火分區，超(chao)長的走廊，以及(ji)在自(zi)然排(pai)煙(yan)(yan)(yan)不能滿足其需(xu)(xu)求的情況(kuang)下加機械式(shi)(shi)排(pai)煙(yan)(yan)(yan)系統。可開式(shi)(shi)排(pai)煙(yan)(yan)(yan)口加排(pai)煙(yan)(yan)(yan)閥形(xing)式(shi)(shi)，也(ye)可常閉的板式(shi)(shi)電動(dong)排(pai)煙(yan)(yan)(yan)口形(xing)式(shi)(shi)。可配合地(di)下導流風機一起使用(yong)。地(di)下室，需(xu)(xu)配合補(bu)風設備一起使用(yong)。

雙(shuang)速(su)風(feng)(feng)機使用問(wen)題。有時(shi)(shi)候會遇到 排(pai)風(feng)(feng)兼排(pai)煙(yan)風(feng)(feng)機，或者(zhe)送風(feng)(feng)兼補風(feng)(feng)風(feng)(feng)機。可以(yi)(yi)使用共同(tong)(tong)(tong)(tong)管(guan)道(dao)，也可以(yi)(yi)設置(zhi)不同(tong)(tong)(tong)(tong)管(guan)道(dao)。均在(zai)平時(shi)(shi)和(he)火(huo)災時(shi)(shi)開啟不同(tong)(tong)(tong)(tong)轉速(su)，以(yi)(yi)滿足進(jin)行不同(tong)(tong)(tong)(tong)的工作需求。