2016.09
23 / 28
13.1. Diagnosing and Fixing Table
PROBLEMS
INDICATIONS
POSSIBLE REASON
OTHER RESONS and REMEDIES
NO AIR
FLOW
Motor is not
working
No current
No power
Check the power supply
Thermal protection is open
The cables are defected which contacts
motor
Contactors or terminal are not tight
Control Panel Off
Controller cable fault
Check the controller cable and behind
socket, it may work off or defected.
LOW AIR
FLOW
Pressure loss in the ducts are
higher than calculated
Check and compare the external static
pressure according to Table 3.1 Check
the duct design
Filters clogged or dirty
Clean filter or change it if necessary
Too much
leakage at the
pressure side of
system
Filter doors are not closed or
duct connections are not
completed
Check the doors and duct connections.
HIGH AIR
FLOW
Duct resistance is very low than
expected
Check and compare the external static
pressure according to Table 3.1 Check
the duct design.
Too much
leakage at the
suction side of
system
Duct connections are not
completed
Check the duct connections
Overcurrent of
fan motors
Supply voltage is low
Engine is over loaded. Measure the
current taken by engine.
Grills are not installed
Install the grills
Filters are not installed
Put the filters in
LOW
PRESSURE
FAULT
On the controller
screen
“Low
Pressure’’
Case of Insufficient Air Flow
Be sure that fans working, check the
filters and system
Others
Contact with the manufacturer
HIGH
PRESSURE
FAULT
On the controller
screen “High
Pressure’’
Case of Insufficient Air Flow
Be sure that fans working, check the
filters and system
Others
Contact with the manufacturer