Brochure

199F-27855-10
9. Zone Valves
TAC Erie™ Zone Valves
149
Modulating Spring and Non-Spring Return PopTop, Two-Way and Three-Way VM Assemblies
Flow Patterns
Piping
• The three-way is only configured as normally closed. For normally open configuration to the coil, turn the valve
around. For proportional valves, set the control action (direct or reverse accordingly).
• The valve should be used in a closed-loop system.
• All valves must be piped so the plug closes against the direction of flow. For two-way valves, flow is from port B
to port A. For normally closed three-way valves, B is the service port and A is the bypass port. For normally open
three-way valves, A is the service port and B is the bypass port.
• Three-way VM valves must be piped in a mixing configuration, not diverting.
CAUTION: Do not use VM series valves in "open" systems. Excess make-up water may cause damage to the
valve.
Follow proper water treatment practices and system procedures. Refer to document F-26080; EN205,
Water and
Steam System Guidelines.
Note:
Normally open actuators are not to be used on three-way valves to achieve normally open configurations.
Use a normally closed actuator and pipe as shown in Figure-2.
Figure 1 Two-Way Valve Normally Closed. Figure 2 Two-Way Valve Normally Open.
Figure 3 Three-Way Valve
B Port Piped to Coil Outlet
Normally Closed.
Figure 4 Three-Way Valve
A Port Piped to Coil Outlet
Normally Open
TAC
Erie™
Zone
Valves
Spring Return
COIL
A
B
Spring Return
COIL
A
B
Spring Return
COIL
A
B
Spring Return
COIL
AB
Zone Valves
F-27411-3 © Copyright 2007 TAC. All Rights Reserved
Erie™ PopTop, 2/3-Way VM SR/NSR
Assembly Flow Pattterns
9. Zone Valves