Tsarin thermocouple mai fashewa da tsarin thermocouple mai haɗuwa, ka'idar ta zama daidai ce, bambancin shine cewa akwatin fashewa mai fashewa (gida) yana amfani da tsarin fashewa na musamman, akwatin fashewa yana da ƙarfin aluminum mai ƙarfi ya mutu, ramin yana da isasshen sarari na ciki, kauri na bango da ƙarfin inji, zafi na roba mai hatimi ya dace da ƙa'idodin fashewa. Saboda haka, lokacin da fashewar gas a cikin akwatin, matsin lamba na ciki ba zai lalata akwatin ba, kuma zafi da aka samar ba zai iya yaduwa da fashewa ba.