Piper Navajo PA-31 Service Manual page 970

PIPER NAVAJO SERVICE MANUAL
TABLE XIII-I. TROUBLESHOOTING CHART (HEATING SYSTEM) (cont.)
Trouble
Cause Remedy
Ventilating air blower
fails to run. (cont.)
Motor burned out. Remove blower assembly
and replace motor. (Re-
fer to Paragraphs 13-40
and 1347.)
Defective radio-noise
filter.
Replace filter.
Combustion air blower
fails to run.
Faulty wiring to motor.
Inspect and replace
faulty wiring.
Poor ground connection.
Worn motor brushes.
Blower wheel jammed.
(Usually indicated by
hot motor housing.)
Defective radio-noise
filter.
Faulty or burned-out
motor.
Tighten ground screw.
Be sure that any metal
preservative has been
removed for a good
ground connection.
Replace motor brushes.
(Refer to Paragraph
13-26, Step b.)
Overhaul the combustion
air blower. (Refer to
Paragraphs 13-41 and
13-48.)
Replace filter. (Refer to
Paragraphs 13-41 and 13-48.)
Remove combustion air
motor for overhaul or
replacement of motor.
(Refer to Paragraphs
13-26, 13-41 and 1348.)
Heater fires but burns
unsteadily.
Insufficient fuel supply.
Inspect fuel supply to
heater, including shut-
off valve, solenoid
valve and fuel lines.
Make necessary repairs.
Reissued: 10/12/79
HEATING AND VENTILATING SYSTEM
5D16