Steam - Typical Modulating Valve Piping - Daikin AVV Installation And Maintenance Manual

Steam – Typical Modulating Valve
Piping
The optional factory supplied Daikin controls with a
2-way Modulating steam valve is furnished normally
open to the coil. When the valve is de-energized (off)
there is full flow through the coil. Energizing the valve
reduces the steam flow in a modulating fashion
CAUTION
Refer to the arrow on the modulating valve body to determine the
direction of flow. If the valve is mounted improperly, the unit will
not operate properly and damage to the valve may result.
The valve should be installed so that there is a 2"
(51mm) minimum clearance to remove the actuator form
the valve body. Provide unions for removal of unit coil
and/or control valve as a future service consideration.
Steam connections may be same end as cooling coil
connections, but are recommended to be opposite end
to facilitate piping. When using Daikin factory controls,
they must be opposite end. The modulating valve
accessory must be field installed on the unit for which it
was selected.
Figure 82: Typical 2-Way Steam Modulating Valve Piping
Supply
Shutoff Valve
A
AB
Steam Trap
Shutoff Valve
Return
IM 817-7
Unions
Unit Coil
Supply
Return
Equalizing Line
Figure 83: Same End Connections – Model AV 68/69 Coils
Figure 84: 2-Way Steam Modulating Valve Control - Same
End Drain Connection (Piping Within Unit End
Compartment)
In Steam Systems:
The optional factory-supplied Daikin controls Modulating
Control Valve for steam applications is the 2-way type. It
is shipped separately from the unit ventilator to help avoid
shipping damage, yet provide the installer with maximum
flexibility in making the field piping connection. Before
proceeding, see Figure 82
33, as well as the job-specific piping drawings.
32
through Figure 87 on page
www.DaikinApplied.com