Johnson Controls York VERSECON YSWD 012, Installation Operation & Maintenance

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JOHNSON CONTROLS
FORM 145.05-NOM1 (708)
3. Connect a second tube to low side pressure tap
of the transducer and route the tube to a location
where you want the under floor pressure to be refer-
enced to. This may be atmospheric or the pressure
in the condition space above the floor. If there is a
second transducer 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.
RETURN, OUTDOOR, SUPPLY AIR, AND MIXED AIR
SENSORS
Return Air Sensor
All units are provided with a return air sensor. The
return air sensor is connected to the Unit Control Board
and coiled up and placed in the control enclosure for
shipment.
The sensor must be mounted in a location that will give
a representative return air temperature.
Supply Air Sensor
All units are provided with a supply air sensor. The
supply air sensor is wired to the Unit Control and
mounted in the supply air section of the unit.
Mixed Air Sensor
All units are provided with a mixed air sensor. The
mixed air sensor is wired to the Unit Control and
mounted in the inlet section of the unit.
Outdoor Air Sensor
The outdoor air sensor is optional and can be ordered
with the unit. The sensor is standard when an air-side
economizer is ordered. The outside air sensor is shipped
loose in a package and is located on the floor of the fan
section.
The sensor must be mounted in a location that will give
a representative outdoor air temperature.
STEAM HEAT
Specification
The steam coil is a factory installed option and is located
on the return side of the unit. The piping extends
outside the cabinet. The location of the steam piping
connections will be on the same side of the unit as
the connections for the condenser water supply. The
wiring for the valve is connected to the Unit Control
and routed to the steam heating coil; however, the steam
heat control valve is not shipped with the unit. The unit
can be ordered and configured for either Tri-State steam
heat or Modulating steam heat. The valve needs to be
selected based on the type of heat, capacity, and steam
pressure. For Tri-State steam heat a floating point valve
would be required that operates off a 24-volt input.
If Modulating steam heat is desired the valve would
operate off a 24-volt power supply with a 2 – 10 VDC
control signal (2 VDC for fully closed and 10 VDC for
fully open).
Steam Piping
Piping must comply with local plumb-
ing codes and ordinances.
Due to the variety of piping practices, it is advisable
to follow the recommendations of local authorities.
They can supply the installer with the proper building
and safety codes required for a safe and proper
installation.
HOT WATER HEAT
Specification
The hot water coil is a factory installed option and is
located on the return side of the unit. The piping extends
outside the cabinet. The location of the hot water piping
connections will be on the same side of the unit as
the connections for the condenser water supply. The
wiring for the valve is connected to the Unit Control and
routed to the hot water valve. The unit can be ordered
and configured for either Tri-State hot water heat or
Modulating hot water heat .