Excessive leak testing or operating pressures may damage these valves and reduce the life of the operating members. Since a high-side test pressure differential of approximately 350 psi or higher will force the DBV open, the maximum allowable test pressure for DBV are the same as for the high and low side of the system. If greater high-side test pressures than those given in the manufacturer’s specifications are to be encountered, some method of isolating the DBV from these high pressure must be found.
Valve settings and adjustment must be done according to the manufacturer’s recommendations. Proper instrumentation must be used to determine exactly when these valves are open.