Troubleshooting - Beechcraft TRAVEL AIR 95 Shop Manual

TROUBLESHOOTING
HEATER SYSTEM
TROUBLE PROBABLE CAUSE
CORRECTION
1. Blower
runs
but heater
a.
Blown fuse.
a. Check ductstat
operation; check
will not start. combustion chamber and ducts
for
obstructions.
b.
Faulty
ignition unit vibrator.
b. Replace
vibrator,
c. Faulty
ignition unit coil. c.
Remove lead from spark
plug
and
hold
so
e
rk may
jump to
structure. If
a
spark, replace
ignition
unit.
d. Faulty spark plug. d. If
test
in (c) produces spark,
remove and
clean
or replace
spark
plug,
e. Fuel solenoid valve not e.
Check electrical
connections.
energized. Disconnect fuel
line
and check
for
fuel
flow, Replace defective
valve.
f.
Fuel filter
clogged. f.
Clean filter.
g. Spray nozzle clogged. g. Clean
spray
nozzle.
h. Insufficient combustion air.
h.
Remove
obstructions
or repair
leaks.
2. Heater will not shut off
a. Defective
ductstat.
a.
Connect
voltmeter
across
automatically. ductstat leads and operate
con-
trol.
As
the
ductstat
is pulled
out,
voltage should decrease.
If not,
replace ductstat.
3. Heater
backfires
inter-
a. Loose
connection
in control
a.
Check electrical
connections.
mittently, circuit
or
loose ignition
lead
to
spark
plug.
b. Mixture
too
rich. b. Make
checks
in item 4 below.
4. Fuel mixture
too
rich;
a. Restriction in combustion
a. Check
iris valve.
Check
ducts
exhaust
smudges
fuselage, air duct.
for obstructions.
b. Restriction
in exhaust duct. b. Check
exhaust
outlet.
c. Loose core in fuel nozzle. c. Clean nozzle. Make
sure core
is seated
tightly
in shell.
5. Heater
produces
a. Thermostat not properly a. Adjust
thermostat.
inadequate heat.
adjusted.
b. Fuel filter partially b.
Clean filter.
clogged,
c. Restriction in fuel lines.
c. Clean
line
or
otherwise
remove
restriction.
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