Yakatemerwa kumuswe mugumo weiyo drainage pombi, iyo flap yelvha ine basa rekudzivirira kudzokera kumashure kwemvura yekunze. Iyo yekuvhota inovhiringidzwa inonyanya kuumbwa nezvikamu zvina: Chigaro, valve ndiro, yemvura seal mhete uye hinge. Maumbirwo akakamurwa kuita denderedzwa uye matinji.

. Kudonhedza matanho: kudhonzwa kubva kune yekutanga chimney kudhirage matsime ematsime, hapana mamwe midziyo yekudonha