BERMAD 720 - Higher Zone Installation; Lower Zone (Two-Stage) Installation

BERMAD Waterworks
700 Series
Model 720
For high differential pressure systems, see BERMAD publication 720-PD Proportional Pressure Reducing Valve.
For high pressure systems, see BERMAD publication 820 Piston Actuated Pressure Reducing Valve.
Higher Zone Installation A
In addition to the municipal pressure reducing system for a high-rise building, BERMAD recommends the
system also include:
■
Parallel Redundant Branches ensuring uninterrupted supply by enabling unskilled personnel to temporarily
shut off one of the branches.
■
Emergency System including a downstream pressure switch and an Emergency Valve Model 720-PD-59.
❏
Pressure Switch [6] signals a control panel of excessive downstream pressure.
❏
Emergency Valve [2] is fully open during normal operation. Triggered by the control panel, it becomes a
proportional pressure reducing valve.
[1] Strainer Model 70F
[2] Emergency Pressure Reducing
Valve Model 720-PD-59
[3] Proportional Pressure Reducing
Valve Model 720-PD
[4] By-Pass Proportional Pressure
Reducing Valve Model 720-PD
[5] Primary Relief Valve Model 73Q
[6] By-Pass Relief Valve Model 73Q
[7] Pressure Reducing Valve
Model 720
[8] By-Pass Pressure Reducing
Valve Model 720
[9]
Relief Valve Model 73Q
[10] Pressure Switch
[1] Strainer Model 70F
[2] Emergency Pressure Reducing
Valve Model 720-PD-59
[3] Pressure Reducing Valve
Model 720
[4] By-pass Pressure Reducing
Valve Model 720
[5] Relief Valve Model 73Q
[6] Pressure Switch
Control Panel
[1]
[2]
[3]
[5]
[6]
[4]
[5]
[3]
[3]
[4]
[7]
[7]
Control Panel
[1]
[2]
[5]
[6]
[8]
[9]
[9]
[3]
[5]
[10]
Lower Zone (Two-Stage) Installation B
When dealing with high differential pressure systems in lower zones of a high-rise building, BERMAD recommends a
two-stage pressure reducing system. In addition to the typical higher zone installation, this high differential pressure
system also includes:
■
Proportional Pressure Reducing Valve Model 720-PD, as the first pressure reducing stage, absorbs part of the
high differential pressure. By spreading the load of pressure reducing onto two components, cavitation damage and
noise are reduced.