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VRW2 DYNAMIC PRESSURE- REGULATING FLANGED CONTROL VALVES
TYPICAL SPECIFICATIONS
23 00 00 HEATING, VENTILATING, AND AIR-CONDITIONING
(HVAC)
23 09 00 Instrumentation and Control for HVAC
23 09 13 Instrumentation and Control Devices for HVAC
23 09 13.33 Control Valves
Multi-Turn, Dynamic Pressure-Regulating Wafer-Flanged
Control Valve
Mounting and Wiring
1. Valves shall be available with wafer-flanges for use with
either ANSI/ASME 125/150 or ANSI/ASME 250/300 pipe
flanges in sizes from 2-1/2 up to 6 inches (DN65 to
DN150). Each wafer flange shall be usable with either of
two successive pipe sizes.
2. The valve shall have an integral differential pressure reg-
ulator to maintain constant pressure drop across valve
seat to decouple valve flow from system pressure
changes. Regulator will be constructed from 316 stain-
less steel with a rolling diaphragm and operate under
positive pressure. Regulator shall be located above axis
of pipe with 1/4-in. ISO test port fittings to allow pressure
measurement and venting. Control accuracy shall be +/-
5% or better.
3. Valves shall use a non-rising stem, characterized plug
with equal percentage flow control characteristic. Valve
trim shall be stainless steel.
4. Valve bodies shall have static pressure rating of 580 psig
(4000 kPa) at 248°F (120 C).
5. Maximum operating differential pressure rating shall be
no less than 58 psid. Close-off pressure shall be 100
psid minimum, at no more than 0.2% leakage.
6. Valve stem seals shall be a combination of EPDM and
Nitrile O-rings.
7. Actuators shall be six turn rotary type requiring neither
crank-arm nor linkage and direct mount to the valve
actuator bracket.
8. Actuators shall provide screw terminal wiring connec-
tions with adapters for flexible conduit where mechanical
protection is required by local codes.
9. Valve actuator shall be capable of operating on 24 Vac
Class II power, in both electronic fail-safe and stay-in-
place configurations. Actuator fail-safe action in the
event of power failure shall be field-selectable normally
open or normally closed.
Control
1. The actuator shall provide two-position, floating, analog
or digital proportional control. Analog proportional control
refers to direct acceptance of 2-10 Vdc or a 4-20 mA
62-3116—01
input signal. Digital proportional control refers to direct
acceptance of 24 Vac pulse-width-modulated input sig-
nal. Floating control refers to direct acceptance of 24 Vac
pulsed open and close commands from a tri-state
(SP3T) controller. Two-position control of non-fail safe
actuators shall be in the form of 24 Vac power controlled
by SPDT switch.Two-position control of fail safe actua-
tors shall be in the form of 24 Vac power controlled by
SPST switch.
2. Flow valve shall have minimum 50:1 rangeability with an
equal percentage flow characteristic. Actuator shall have
field-adjustable signal zero and span adjustments.
3. Flow settings shall be field-selectable from 50 unique
settings.
4. Proportional and floating control actuators shall provide
a 2-10 Vdc/4-20 mA feedback signal.
5. Actuators shall provide analog proportional, PWM, float-
ing, or two-position control through wiring options.
6. Actuation will be available with electronic fail-safe opera-
tion.
Other
1. Valves may not be installed with stems below the hori-
zontal plane to prevent actuator damage due to stem
seal leakage, or accumulation of particulate in the stem
packing.
2. A water filtration and treatment system shall be installed
and operated according to the requirements of Division
23 25 13, Water Treatment for Closed-Loop Hydronic
Systems. These requirements shall meet or exceed
European Norm VDI 2035. The presence of excess rust
in the system will void the manufacturer's warranty.
3. Run time shall be constant and independent of: load,
temperature, and supply voltage (within specifications).
4. All valves and actuators shall be manufactured under
ISO 9001 International Quality Control Standards.
5. Actuators shall have a one year warranty from date of
installation.
6. Accessories Identification tags shall be available for all
valves; tags shall be indelibly marked with gpm, model
number, and tag location.
7. Valves and actuators shall be as supplied by Honeywell.
Balancing Valves (Mechanical
section)
Balancing valve installation and commissioning shall not be
required when dynamic pressure-regulating control valves are
used throughout a building. The balancing report, as required,
shall confirm design coil flow by direct measurement across (a
representative sample of/all) coils in the building.
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