Pressure Control Methods - Price PCV Series Manual

PRESSURE CONTROL VALVE
PRODUCT OVERVIEW

Pressure Control Methods

Open Return Bypass Method
In the case of an "open return" system,
the duct work is ducted so that the
return side of the PCV (pressure
controller) is open to the plenum. (See
Figure 1.1) This means that the air will
get bypassed through the PCV and
then into the ceiling plenum. This type
of system is quite common and easier
to duct.
Ducted Return Bypass Method
In the case of a ducted return system,
the duct work would be ducted so that
the return side of the PCV (pressure
controller) is ducted back to the unit,
either the rooftop unit or the air handler.
(See Figure 1.2) This means that the air
will get bypassed through the PCV and
then back into the unit. One thing to
consider in this type of ducting method
is that this could cause the coils in the
air handling unit to freeze up if too much
air is returned at a very low temperature
or similarily in heating mode too much
warm return air could trip the heat high
temp limits. The air handler should
be fitted with a low temp cutout for
cases like this to prevent the coils from
freezing.
2 PRESSURE CONTROL VALVE - Manual | priceindustries.com
FIGURE 1.1 - OPEN RETURN BYPASS METHOD (SEQUENCE 1550)
Return
FIGURE 1.2 - DUCTED RETURN BYPASS METHOD (SEQUENCE 1550)
Return
Pressure Control Valve
Supply
P
Pressure Control Valve
Supply
Static Pressure Tubing
P Static Pressure Sensor
P
Static Pressure Tubing
Static Pressure Sensor
P