The Vokera safety relief valve for Procombi, Vision, Mynute, Compact, Excel, Mynute EHE, Linea, Sabre, Unica, Mynute i, Mynute HE, Easi-Heat Plus, Maxim, Vibe, Evolve and Vision Plus boilers. The pressure relief valve helps to control pressure in a closed system by proportionally opening to relieve excess pressure, preventing catastrophic malfunction.