Thermostat ihindura ingano y'amazi yinjira muri radiator hakurikijwe ubushyuhe bw'amazi akonje kandi igahindura urwego rw'amazi azenguruka kugira ngo ihindure ubushobozi bwo gusohora ubushyuhe bwa sisitemu yo gukonjesha no kwemeza ko moteri ikora mu rugero rukwiye rw'ubushyuhe. Thermostat igomba kuguma mu buryo bwiza bwa tekiniki, bitabaye ibyo byagira ingaruka zikomeye ku mikorere isanzwe ya moteri. Iyo valve nkuru ya thermostat ifunguwe bitinze, bizatuma moteri ishyuha cyane; Iyo valve nkuru ifunguwe kare cyane, igihe cyo gushyushya moteri kizaba kirekire kandi ubushyuhe bwa moteri buzaba buri hasi cyane.
Muri rusange, intego ya thermostat ni ukurinda moteri gukonja cyane. Urugero, nyuma yuko moteri ikora neza, moteri ishobora gukonja cyane mu gihe cy'itumba nta thermostat ifite. Muri iki gihe, moteri igomba guhagarika by'agateganyo gutembera kw'amazi kugira ngo ubushyuhe bwa moteri butari hasi cyane.