Wiring Connections For B39D59 Heater Operation Test - Piper Navajo PA-31 Service Manual

Figure 13-36. Wiring Connections for B39D59 Heater Operation Test
13-52. OPERATIONAL TEST. (Refer to Figure 13-33, 13-34, 13-35 or 13-36.)
a.
Connect the heater to the test set-up as shown in Figure 13-33. Make sure the combustion air
blower is mounted securely and that
the
heater
is clamped to its supporting stand.
b. Insert the duct switch in
the sheet metal extension
the tube at the location shown in Figure 13-33.
c.
Connect components and heater as outlined
in the wiring connection
diagram, Figure 13-34,
13-35 or 13-36. The power supply switch
should be open.
d.
Connect the power source to the heater.
e. Disconnect wire lead from terminal "3" on the heater side of heater terminal strip to prevent the
heater from lighting and close the power source switch to check operation of blowers. The combustion air
blower and ventilating air blower should operate at full speed with no blower wheel interference. If either
blower fails to run, locate and correct the trouble before proceeding with the test.
f.
Connect a voltmeter from open side of combustion air pressure switch terminal to ground to
determine if the switch is closed, which would be indicated by a full voltage reading on the meter. If a full
voltage reading is not obtained, either the combustion air supply is inadequate or the switch is defective or
improperly adjusted. Make necessary corrections.
g.
Observe the manometer connected to the ventilating air pressure tap, which should show a
reading of 1.1 inches of water (minimum) at rated voltage.
h. Observe the manometer connected to the combustion air tube tap, which should show a reading
of 1.5 inches of water (minimum) at rated voltage.
i. Open the power supply switch and reconnect the terminal lead disconnected in preceding Step e.
j.
Close the power supply switch and turn on the fuel supply; The heater should light within five
seconds (may require slightly longer for air to be purged from fuel lines on the first trial).
k. Observe operation of duct switch, which should control heater operation according to the switch
setting.
Reissued: 10/12/79
HEATING AND VENTILATING SYSTEM
PIPER NAVAJO SERVICE MANUAL
5D11