19, Initial Start Up - Nordyne O4MD Installation, Operation And Maintenance Manual

It is possible and acceptable to use a single blower speed 4.
for both heating and cooling modes. The simplest
method to connect the wiring from both modes is to use a
"piggy-back connector" accommodating both wires on a 5.
single motor tap. It is also acceptable to connect the 6.
selected motor speed with a pigtail joined to both heating
and cooling speed wires with a wire nut. As a safety
precaution against accidental disconnection of the wires 7.
by vibration, secure the wire nut and wires with a few
wraps of electricians tape.
IAWARNINGI
DO NOT CONNECT POWER LEADS BETWEEN
MOTOR SPEEDS. THE NEUTRAL WIRE MUST
ALWAYS BE CONNECTED TO THE MOTOR'S
DESIGNATED NEUTRAL TERMINAL.
If the joining of the blower speed wiring is done in the
furnace junction box or control box, tape off both ends of
the unused wire.
I_C AUTION ]
DISCONNECT THE POWER SUPPLY TO THE
FURNACE BEFORE OPENING THE BLOWER
ACCESS DOOR TO SERVICE THE AIR FILTER, FAN
AND MOTOR, FAILURE TO SHUT OFF POWER
COULD ALLOW THE BLOWER TO START
UNEXPECTEDLY, CREATING A RISK OF DEATH
OR PERSONAL INJURY,
Do not use the blower speed wires as a source of
power to accessories as electronic air cleaners and
humidifier transformers. The unused motor taps
auto-generate sufficiently high voltages to damage
accessory equipment.
IAC AUTION ]
DO NOT START THE BURNER OR BLOWER FAN
UNLESS THE BLOWER ACCESS DOOR IS
SECURELY IN PLACE,
19. INITIAL START UP
Once the furnace flue pipe, electrical and oil line
connections have been made, use the following
instructions to set up the furnace:
1. Shut off the electrical power to the furnace.
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Install an oil pressure gauge to the pressure port on
the oil pump. (Refer to the oil pump specification
sheet included with the burner instructions).
3. Restore electrical power to the furnace.
=
=
10.
Start the furnace and bleed all air from the fuel oil
lines.
Close the purge valve and fire the unit.
Follow the procedures outlined in 17. - Oil Burner Set
Up, (page 10).
Check the system temperature rise with a pair of duct
thermometers. The temperature rise is the difference
between the return air temperature measured at a
point near the return air inlet, and the supply air
temperature measured near the furnace outlet. The
system temperature rise will typically range between
65°F and 95°F. If the temperature rise is too high, the
airflow must be increased. If the temperature rise is
too low, the fan should be slowed down.
Turn off the oil burner. Observing the duct
thermometer in the supply air stream, note the
temperature at which the blower fan stops. The fan
adjustments are made by manipulating the FAN ON
and FAN OFF levers. EXAMPLE: If the "FAN OFF"
setting is observed to be 100°F, and the actual "fan
off" temperature as indicated by the duct
thermometer is 110°F, the "FAN OFF" setting on the
fan / limit control can be reset to 90 ° (one notch
clockwise), to cause an actual fan shutdown at
100°F. Normally, the 'FAN ON" setting is set to be
approximately 30 ° higher than the "FAN OFF" setting.
Some downflow applications require a greater
difference; 40 ° - 50°F.
To check the operation of the limit switch, shut off
power to the furnace. Temporarily remove the neutral
wire from the direct drive blower motor. Restore the
electrical power to the furnace and set the thermostat
above room temperature. After three or four minutes
of burner operation, the limit control should turn the
burner off. Progress towards a high limit shut down
can be monitored by watching the dial on the fan /
limit control. When the limit function test is complete,
first, shut off electrical power to the furnace, replace
the neutral wire to the blower fan motor, then restore
power. The blower fan will start up immediately.
Once the temperature has dropped, the oil burner will
resume and continue until the thermostat is satisfied.
Restore the thermostat setting to a comfortable
temperature.
Set the thermostat heat anticipator to 0.3 A, or follow
the procedure outlined in 9. Electrical Connections,
(page 8).
NOTE: THE FURNACE SHOULD BE RUN THROUGH
AT LEAST THREE FULL CYCLES BEFORE
LEAVING THE INSTALLATION, TO ENSURE
THAT ALL CONTROLS ARE OPERATING
PROPERLY AND AS EXPECTED,
] 2 153B0801