Page
18
ML442 | v5k
Expo Technologies UK
T: +44 (0) 20 8398 8011
Expo Technologies US
T: +1 (440) 247 5314
Expo Technologies China
T: +86 532 8906 9858
Fault Finding (CF)
Is the PE
strong enough?
Is the Pressure /
Flow Sensor out
of calibration or
faulty?
Pressurized/Purging indicator
will not turn green during
start up
Call Expo
Is the supply
pipe to the air
inlet as least
12mm I.D?
Is there
excessive
leakage from
the PE?
Is the air supply
pressure
incorrect?
No
Check the air
supply pressure
at the inlet to the
MiniPurge is
stable between
4 - 8 Barg /
60 - 115 psi
Yes
Replace pipe
work
No
Yes
Any significant
leakage must be
corrected. Check
for leaks down
the cables or
conduit. Ensure
leakage does not
exceed 60 Nl/min
(2 cfm)
Yes
No
Yes
No
The standard
requires that the
PE is tested to
1.5 times the
Relief Valve
opening pressure
e.g. 15 mbarg for
many systems.
Has this been
done?
No
The basic operation of the Pressure Sensor
can be checked by unscrewing the 60mm
diameter diaphragm housing and, by using a
rubber pad, e.g. an eraser, block the 12mm
threaded hole in the top of the valve module.
The valve should operate and the indicator
turn green. If this is correct, the sensor
diaphragm needs recalibrating or replacing.
Yes
