Johnson Controls York VERSECON YSWD 012, Installation Operation & Maintenance

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32
JOHNSON CONTROLS
FORM 145.05-NOM1 (708)
Be sure that tubing complies with local
code requirements. Flame retardant
plastic or metal tubing may be re-
quired. Carefully select the ductwork
sensing point for the pressure sensor.
Improper location of the sensing point
will result in unsatisfactory opera-
tion of the entire variable air volume
system.
The following guidelines should be adhered to:
1. Plastic tubing (1/4” ID) must be run from the high
pressure tap of the duct static pressure transducer
to a static pressure tap (field supplied) in the
supply duct. The static pressure probe should
be mounted two-thirds of the way down the duct
prior to any take off.
2. The sensing probe should be located in a non
turbulent flow area of the duct. Keep several
duct widths away from bends or neck downs.
Mounting Instructions
1. Drill a hole in the duct in a location per the above
guidelines and mount the field supplied duct static
sensor.
2. Clamp a second tube (atmospheric reference)
to the outside of the duct at the location of the
sensing point.
3. Route both tubes along the ductwork and back to
the unit. The duct static transducer(s) are located
in a compartment above the blower compartment
on the right side of the unit.
4. Drill two holes through the unit upright post in the
vicinity of the transducer(s). Each of the tubes
should be routed through a grommet to protect
the tubing and seal the cabinet. The size of the
holes will vary based on the type of grommet
used.
5. Connect the tube from the duct static sensor to
the “high” port on the transducer and connect the
second tube (atmospheric reference) to the “low”
port on the transducer.
6. If the unit has two duct static transducers repeat
the above procedure for the second transducer.
To avoid confusion between “high”
and “low” tubing, it is recommended
that two different tubing colors be used
and that this information be recorded,
along with the sensing point location,
on the master building blueprints.
STATIC PRESSURE TRANSDUCER INSTALLATION
(FLEXSYS UNITS ONLY)
All FlexSys units include a factory mounted static
pressure sensor (SPS1). The unit can also have an
optional second static pressure sensor, (SPS2). The
second static pressure sensor would be used to get an
average of the static pressure in the under floor space.
When two static pressure sensors are used the control
can be programmed to maintain the lowest input, highest
input, or the average of the two inputs. The sensors are
factory wired and require field installation of ¼” ID
sensor tubing to the selected under floor location. A
field supplied static pressure probe and tubing must be
field installed prior to the start up of the unit.
Be sure that tubing complies with local
code requirements. Flame retardant
plastic or metal tubing may be re-
quired. Carefully select the ductwork
sensing point for the pressure sensor.
Improper location of the sensing point
will result in unsatisfactory opera-
tion of the entire variable air volume
system.
Installation Instructions
1. Drill two or four holes through the unit upright
post in the vicinity of the transducer(s). Each of
the tubes should be routed through a grommet to
protect the tubing and seal the cabinet. The size
of the hole will vary based on the type of grommet
used.
2. Connect one of the tubes to the high side pressure
tap of the transducer and route the tube to the lo-
cation in the under floor space where you want to
maintain the specified under floor plenum pressure.
If there is a second transducer repeat the above pro-
cedure for the second transducer selecting another
location for the second sensor.
Installation