Vavu yokulitsa ndi gawo lofunika kwambiri la makina oziziritsira, nthawi zambiri imayikidwa pakati pa silinda yosungira madzi ndi evaporator. Vavu yokulitsa imapangitsa kuti madzi oziziritsira pa kutentha kwapakati komanso kuthamanga kwambiri kukhale nthunzi yonyowa pa kutentha kochepa komanso kuthamanga kochepa kudzera mu throttling yake, kenako firiji imayamwa kutentha mu evaporator kuti ikwaniritse zotsatira za kuzizira. Vavu yokulitsa imayang'anira kuyenda kwa valavu kudzera mu kusintha kwa kutentha kwambiri kumapeto kwa evaporator kuti aletse kugwiritsidwa ntchito molakwika kwa malo oziziritsira komanso vuto la kugwetsa silinda.
Mwachidule, valavu yowonjezera imapangidwa ndi thupi, phukusi lozindikira kutentha ndi chubu choyezera bwino
Mkhalidwe wabwino wogwirira ntchito wa valavu yokulitsa uyenera kukhala kusintha malo otseguka nthawi yeniyeni ndikuwongolera kuchuluka kwa madzi ndi kusintha kwa katundu wa evaporator. Koma kwenikweni, chifukwa cha hysteresis ya kusamutsa kutentha mu envelopu yozindikira kutentha, yankho la valavu yokulitsa nthawi zonse limakhala locheperako pang'ono. Ngati tijambula chithunzi cha nthawi ya valavu yokulitsa, tidzapeza kuti si yokhota yosalala, koma mzere wozungulira. Ubwino wa valavu yokulitsa umawonekera mu kukula kwa mafunde. Kukula kwa mafunde kukakhala kwakukulu, kumachepetsanso momwe valavu imagwirira ntchito komanso kuipa kwa khalidwe.
