Piper Navajo PA-31 Service Manual page 676

PIPER NAVAJO SERVICE MANUAL
TABLE X-III.
TROUBLESHOOTING CHART (PRESSURE SYSTEM) (cont.)
Trouble
Cause Remedy
De-Icers
inflate slowly.
(Inflation time - 6 sec -
onds. ) (cont.)
De-Icer pump valve not
functioning.
Check fitting in De-Icer
port for proper instal-
lation.
Low air pump capacity.
De-Icer puncture.
Check performance to
manufacturers
spec-
ifications.
Repair per specification
or replace.
De-Icers inflate,
indi-
cator light does not
function. (Ascertain
that De-Icer
boot
switch is "ON".)
Indicator lamp burned
out.
System pressure
not
being reached.
Replace lamp.
Check "De-Icers inflate
slowly" above.
Pressure switch not
functioning.
Wires loose or broken.
Poor grounding of
pressure switch.
Make electrical test and
replace if required.
Make electrical test.
Repair or replace
broken wires. Check
for proper ground.
De-Icers deflate slow-
ly.
Pressure regulator set
too low.
Re-adjust pressure re-
regulator.
Piping or lines partially
blocked.
Overboard line from
control valve partially
blocked.
Inspect and blow out
lines.
Inspect and blow out
lines.
INSTRUMENTS
Reissued: 10/12/79
3E14