Burn Test - Piper TWIN COMANCHE PA-30 Service Manual

PIPER TWIN COMANCHE SERVICE MANUAL
13-77.
FUEL CONTROL VALVE LEAK TEST. Remove the fuel control valve
from the heater, or test the valve separately before reassembly,
during the over-
haul.
Proceed with test as follows:
a.
Connect the control valve to the fuel source.
b. Install the short heater fuel line (Refer to Figure 13-10, Ref. 17. ) in the
fuel control valve outlet, in its normal position.
Support the valve in its normal
mounting position so that fuel from the fuel line will drip into a glass graduate.
NOTE
The valve must be supported in a normal position so
that a line through the mounting screw holes of the
bracket will be level.
Failure to test the valve in its
proper position willaffect the fuel rate and may cause
rejection of good equipment.
c.
Ground the body of the fuel control valve and apply a test voltage to each of
the solenoid leads. A distinct click should be heard when the solenoids areener-
gized.
d. Turn on the fuel pressure and energize both solenoids at once. Allow fuel
to flow through the valve for a few seconds, then de-energize both solenoids.
One or two drops of fuel may fall from the outlet within 15 seconds after the so-
lenoids are closed. After 15 seconds, a drop of fuel may form, but it should not
fall.
If the valve does not shut off completely it must be replaced.
13-78.
LOCKOUT OVERHEAT SWITCH. Thetestforthelockoutoverheatswitch
is described in Paragraph 13-64.
This test is normally performed during over-
haul, before the switch is installed, but the switch may be removed and tested at
anytime its operation is in doubt.
13-79.
BURN TEST.
Shut the heater off and remove the cover from the venti-
lating air blower inlet.
Allow time for the heater to cool. Proceed with "burn
test" as follows:
a.
Turn on the heater switchand adjust voltage to 12 volts. Start timing heat-
er acton from the moment the switch is turned on.
b. The current draw should not exceed 13 amperes.
c.
Ignition should occur within 20 seconds from the moment the switch is turn-
ed on.
d. The flame detector switch should close more than 8 seconds, out less than
25 seconds, from the instant the heater ignites.
HEATING AND VENTILATING
Issued: 12/29/72
4C1