Measurement Modes in the Main Menu
34
6.5
Option
“
4 Pa
Test
“
Fig. 34: Wöhler DC 410
FLOW
with capil-
lary hoses
The 4 Pa Pressure Test is a simple control of the
underpressure limit 4 Pa for the confirmation of a
sufficient combustion air supply.
In a closed room or in connected rooms, simulta-
neous operation of non-roomsealed heating appli-
ances and ventilation and air conditioning systems
can cause dangerous underpressure.
With the 4 Pa Pressure Test the underpressure
value can be controlled. The readings are plotted
in a graph during about 4 minutes, and can be
saved and print out afterwards.
NOTE!
For the 4 Pa Test two capillary hoses must be
connected to the Wöhler DC 410
FLOW
.
The 4-Pa Test measures the pressure difference
between the room where the fireplace is installed
and another room which is not connected (e.g.
outside air, stairway etc.) Before starting the
measurement, two flexible capillary hoses must
be connected (see accessories). The pressure
sensor of the meter will measure the pressure
difference.
Fig. 35: Initial display of the 4 Pa test
Before starting the measurement:
1.
Select 4 Pa Test in the main menu of the DC
410
FLOW
The current differential pressure reading will
be displayed.
2.
Connect the capillary hose leading to the
reference point (stairway or outside air), to the
negative pressure socket (fig. 1, part 10).
3.
Connect the second capillary hose to the
positive pressure socket (fig. 1, part 9). The
second hose stays in the room where the fire-
place is installed. With this hose the march of
pressure will be recorded.
Underpressure in the fireplace room in relation to
the pressure at the reference point will lead to a
negative differential pressure.
Capillary
hose inside
pressure
Capillary
hose
outside
pressure
