Brochure

7
PICV applications
for Hydronic Flow
Optimization
AHU Applications
Air Handling Unit with PICV direct control
This is a common use case for PICV in North American
hydronic systems. Shown here is a simplified diagram
of an AHU coil installation with PICV, distribution pump, and
other accessory devices. Space temperature is controlled by
a sensor, allowing for the control system to call for higher
or lower outlet air temperature.
The PICV in this application would replace the control valve
and static balancing valve and combine into one device.
This singular device would then be the central point for flow
control of this particular AHU as well as the central device
taking action to stabilize flow through use of its automatic
pressure regulator. This would free the control system up in
its operation mode to focus on the necessary flow control to
best match the load present in the space.
Air Handling Unit with PICV injection circuit
This is a slightly different variant of the AHU application.
In this case, there is a secondary distribution pump as well
as an injection pump in the AHU circuit to facilitate BTU
injection into the loop alongside temperature mixing.
In this particular example, heating is being dealt with and
in order to maintain uniform temperature throughout the
entire coil, the circulation on the secondary circuit is
constant during load periods.
The PICV installed in the return branch of the circuit
eliminates the use of a static balancing valve and
differential pressure control valve. This allows the single
device to regulate flow from the return riser to the primary
return branch and aid in keep overall system delta-T at the
desired levels.
With a more uniform temperature across the entire coil,
particularly for large coil areas, this approach allows for direct
relation between the coil temperature and power output.
Air
Handling
Unit
PICV
Room
Controller
Metering
Station
Primary
Pump
R
S
Air Handling Unit with PICV direct control
Air
Handling
Unit
PICV
Room
Controller
Metering
Station
Primary
Pump
Circulation
Pump
R
S
Injection Circuit
Primary Side
Injection Circuit
Secondary Side
Air Handling Unit with PICV injection circuit