20 ingersollrandproducts.com
PROBLEM SYMPTOM(S) POSSIBLE CAUSE CORRECTIVE ACTION
Apparent controller
display malfunction
Display Blank Blown Fuse Check Fuses
Board Failure Contact your local distributor for
further assistance.
Unrealistic temperature
displayed
Probe loose,o connection
or defective probe
Inspect probe cable and terminal
connection Replace probe
Erratic or inaccurate
temperature readings
Probe not completely in
thermal well
Inspect probe and check readings
against independent source (eg.
temperature analyzer/pyrometer/
ice bath) both in temperature well
and to ambient
Defective probe Replace probe
Unrealistic pressure
displayed
Transducer loose, o
connection or defective
transducer
Inspect transducer cable and
terminal connection
Replace transducer
High pressure drop
across dryer
Outlet pressure substantially
lower than inlet pressure
System operating tempera-
ture is above 32°F
Inlet and outlet valves not
completely open
Open valves
Inlet and outlet lters
blocked up
Change lter elements
Outlet pressure substantially
lower than inlet pressure
System operating tempera-
ture is below 32°F
Compressor relay / contactor
stuck.
Replace relay / contactor.
Microprocessor Control relay
bad
Replace relay
Probe not completely in
thermal well
Inspect probe and check readings
against independent source (eg.
temperature analyzer/pyrometer/
ice bath) both in exchanger well
and to ambient
Problem persists Turn dryer o and consult your
local distributor for further
assistance
Condensate drain does
not re
Inlet / outlet pipe internal
diameter too small causing
air-lock or back pressure.
Replace with larger diameter
piping.
Excessive use of bends /
elbows in inlet / outlet pipe
work causing air-lock/ back
pressure.
Reduce the amount of bends and
elbows.
Outlet pipe too long / too
high causing back pressure.
Recongure condensate piping.
More than one condensate
source connected providing
alternative path for
condensate.
Reroute condensate to eliminate
secondary path. Install check
valves as required.
11.0 TROUBLESHOOTING
120.26A D4290NCHPW400F Installation Operation and Maintenance Manual