Igumbi okomisa i-thermal heater yamafutha iyisitsha esisha, esiphephile, esisebenza kahle kakhulu nokonga amandla, ingcindezi ephansi (ngaphansi kwengcindezi evamile noma ingcindezi ephansi) futhi inganikeza amandla okushisa aphezulu okushisa kwesithando somlilo esikhethekile sezimboni, ngamafutha okudlulisa ukushisa njengesiphathi sokushisa, ngokusebenzisa iphampu yokushisa ukuze ijikeleze isithwali sokushisa, ukudluliswa kokushisa emishini yokushisa.
Isistimu kawoyela yokudlulisa ukushisa okushisa kagesi yakhiwe ngesifudumezi sikagesi esingaqhumi, isithando somlilo esithwala ukushisa okuphilayo, isishintshi sokushisa (uma sikhona), ibhokisi lokusebenza elingaqhume endaweni, iphampu kawoyela eshisayo, ithangi lokunweba, njll., okungaba esetshenziswa kuphela ngokuxhunywa kugesi, ukungenisa nokuthekelisa amapayipi omthombo ophakathi nendawo kanye nezinye izixhumanisi zikagesi.