43
Valves
WATER VALVES — Water valve assemblies are shipped
with the unit for field installation. All factory-supplied valves
are fully modulating and capable of being positioned at any
point within the travel range of the valve. Each valve is
shipped complete with an actuator and any required linkage.
The equal percentage characteristics of the modulating
valves provide close temperature control on heating, cooling or
reheat unit ventilator coils.
In case of power failure, a return spring sends the valve to
its normal position. The normal position is defined for each
control sequence.
Water Valve Actuators
— Water valve actuators are factory-
mounted on factory-supplied valve assemblies. The valve and
actuator assemblies are modulating spring return for all water
and steam applications. Valves are factory supplied.
All valves use actuators with reversible electric motors. The
control provides proportional control to the electric motor
which receives a tri-state signal from the control.
All valves have a spring return feature that allows them to
return to a normal positions (normally closed) upon loss of
power.
All valve assemblies have electrically powered actuators.
Each actuator is factory-wired and operates its valve through a
linear stroke.
Each water valve actuator features a magnetic clutch to ex-
tend the life of the motor and gear train. A manual override le-
ver and position indicator facilitates field setup.
On chilled water or hot water applications, the valve actua-
tors can be mounted in any position above the center line of the
valve body. For steam applications, mount the actuator above
the centerline of the valve body and at least 45 degrees from
vertical. This position prevents exposing the actuator to ex-
treme heat. Refer to Fig. 32.
.
Water Valve Wiring — Valve wiring is determined by the
actual valve selected and the control sequence.
All valves are factory-wired to the control module and
tested.
Water valve specifications and dimensions are found in
Table 17 and Fig. 34.
Table 17 — Water Valve Specifications
To prevent electric shock and equipment damage, discon-
nect the power to the control before performing any work
on valve assemblies.
The manual positioning lever on all water valves should
only be used when controller power is OFF. DO NOT
attempt to move this lever when controller power is
applied. If the position lever does not move freely for man-
ual positioning when the power is off, remove the valve
cover and push the solenoid plunger down using a small
screwdriver inserted in the slot below the solenoid.
DO NOT install valve assembly where excessive moisture,
corrosive fumes, and/or vibration are present.
INSTALL all 2-way valve assemblies so that they close
against system flow. Proper flow direction is from inlet
‘B Port’ to outlet ‘A Port’.
ALWAYS install 3-way mixing valve with 2 inlet flows
and one outlet. Proper flow direction is: inlet ‘B Port’ to
coil. Inlet ‘A Port’ to supply. “Common Port’ to return. See
Fig. 33.
FEATURE SPECIFICATION
Application Hot or Chilled Water, up to 50% Glycol
Fluid Temperature
Minimum 32 F (0° C)
Maximum 200 F (93 C)
Flow Type Equal % Service Port Linear Bypass (3-way only)
Static Pressure Limits 300 psi (20.7 bar)
Current Requirement (24 V Supply) 12 VA (in rush), 100 mA Continuous
Material
Body Forged Brass
Stem Chrome-Plated Brass
Seat Stainless Steel
Plug High Temperature Thermoplastic
Actuator Stainless Steel Base, Aluminum Cover
Maximum Ambient Temperature and Humidity 125 F (52 C) 95% Non-Condensing
Actuator
Voltage
24vac—15%, +10%
50/60 Hz
Power
12 VA inrush at 24 vac
2.5 VA holding
Connections Screw Terminals
Weight 3.0 lb (1360 g)
VERTICAL
45° MINIMUM/
90° MAXIMUM
FROM VERTICAL
DO NOT MOUNT
VALVE HERE
Fig. 32 — Valve Mounting Angle for
Steam Heating Applications
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