Installation and Maintenance Manual

General Information
UV-SVN02C-EN 9
Face and Bypass (Option). The face and bypass option
consist of an actuator, damper blade and 2-position water
valve (option).
During bypass mode, the damper moves to prevent air
from traveling through the coil. The damper blade is
tightly sealed to eliminate heat pickup while in the full
bypass mode.
A two-position isolation valve control (option) further
enhances this system by closing off all water flow to the
coil during full bypass operation. Two-pipe main steam
systems utilize the face and bypass as part of the standard
operation and may incorporate the optional isolation
valve.
Face and Bypass Actuator (Option). The face and
bypass damper actuator incorporates a direct couple
design for the horizontal configurations. The actuator is
provided with electronic protection against overload. It
does not contain, nor require a limit switch. When reaching
the damper end position, the actuator automatically stops.
The gears can be manually disengaged with a button on
the actuator housing. See Table 2 for technical data.
Modulating Water Valves (Option). The modulating
control valve option provides optimum control of hot and
chilled water flow in various heating and cooling
applications. They are designed to provide sinusoidal
valve actuator travel and operate silently, resisting water
hammer.
The actuator on the valve is a 24V, 3-point floating type.
See Ta b l e 3 , p . 9 for more technical data.
Isolation Valves (Option). The isolation valves are two
position 24V, spring return type. They provide added
control in heating and cooling applications when used in
conjunction with the face and bypass damper.
On heating coils and two-pipe change-over applications,
the valve is a normally open type to prevent the coil from
freezing in case of power loss.
For cooling, the valve is normally closed and opens when
there is a call for cooling. See Table 4, p. 10 for more
technical data.
Table 2. Technical data for face and bypass actuator
Power Supply 24 Vac ±20% 50/60Hz
24 Vac ±10%
Power Consumption 2W
Transformer Sizing 3VA (class 2 power source)
Manual Override External push button
Control Signal 3-point floating w/Trane controls
Rotation Angle 95-degree max. Adjustable w/mechanical stop
Torque 35-inch/lb
Rotation Direction Reversible with switch L/R
Position Indication Clip-on indicator
Noise Level Less than 35dB
Table 3. Technical data for modulating water valves
Power Supply 24V - 50/60 Hz
Power Consumption 4W
Maximum Duty Cycle 15%
Operating Ambient Temperature 0°C to 65°C
32°F to 150°F
Min./Max. Fluid Temperatures 1°C to 95°C
34°F to 203°F
Operating Pressure Differential Max. - 4 bar (60 psi)
Pressure Rating Static - 20 bar (300 psi)
Burst - 100 bar (1500 psi)
Flow Characteristics Linear
UV-SVN02_-EN.book Page 9 Thursday, January 24, 2013 4:48 PM