White Rodgers 668 - Manuel (Page 2)

2
Possible Cause of Correction
Trouble
Open circuit in Cell Replace Cell (or Cell Assembly)
of 956 Flame Detector. Do not
disturb position of bracket or
socket assembly.
Flame detector Locate flame detector according
improperly positioned. to the burner manufacturer’s
specifications.
The following control checks should be made after each
installation to insure that the controls are correctly wired
and functioning properly.
1.
Open the main line switch.
2. Adjust thermostat or operating control to call for heat.
3. Operate the manual reset button on top of control.
4. Make certain that high limit control is set at the correct
temperature.
5. Open the hand valve in the oil line. The system is now
ready for the following tests.
A. NORMAL CYCLE:
Close the line switch. The burner should start and
continue to run normally. (If burner starts, establish-
ing flame, but then locks out on safety, make “Flame
Detector Check” at this time.
B. SAFETY TIMING:
1.
Let the burner run for about 5 minutes. Then remove
one of Flame Detector leads from the “F” terminals.
After a time period corresponding to the safety timing
has elapsed, the control should lock out on safety,
stopping the burner.
2. Open the line switch.
3. Replace Flame Detector lead removed in step 1.
4. Wait about 3 minutes. Then operate the manual reset
button on top of control.
C. HIGH LIMIT AND THERMOSTAT CHECK:
1.
Close the line switch to start the burner.
2. Lower the setting of the high limit control to its lowest
setting. This should stop the burner, unless furnace or
boiler temperature is below the minimum setting of the
high limit.
3. Return high limit control to its proper setting. Burner
should restart.
4. With the burner running, turn thermostat to its lowest
setting. This should stop the burner, unless actual
room temperature is below the lowest setting of the
thermostat.
On systems supplying domestic hot water, burner
will continue to run if low limit control is not
satisfied.
INSTALLATION AND WIRING CONT.
All wiring should be done in accordance with local and national electrical codes and ordinances.
LOW VOLTAGE PRIMARY CONTROL LINE VOLTAGE PRIMARY CONTROL
External Line Voltage Wiring External Line Voltage Wiring
TESTING
5. Return thermostat to its proper setting.
D. FLAME DETECTOR CHECK: (This test is not re-
quired if the control performs as described in test
A.)
If the burner starts but the control locks out (stopping the
burner), check the flame detector as follows:
1.
Open the line switch.
2. Connect one end of a wire jumper to one of the “F”
terminals.
3. Start the burner by closing the line switch. As soon as
the flame has been established, connect the other end
of the wire jumper to the other “F” terminal.
The control provides no safety protection with
this jumper installed. Do NOT leave burner in this
condition except for making this check.
If the control still locks out with the jumper installed, the
control should be replaced. If the control does not lock out,
however, check the operation of the 956 flame detector as
follows:
T T F F
ORANGE WIRE
NUTS
THERMOSTAT
FLAME
DETECTOR
FLAME
DETECTOR
FIELD
INSTALLED
JUMPER
LINE VOLTAGE
THERMOSTAT OR
OPERATING
CONTROL
IGN.
TRANS.
WIRE
NUTS
IGN.
TRANS.
PRIMARY
CONTROL
WHITE
BLACK
LIMIT
LINE
HOT N BURNER
MOTOR
ORANGE
PRIMARY
CONTROL
WHITE
BLACK
LIMIT
LINE
HOT N BURNER
MOTOR
T T F F
NOTE
WARNING !
CELL ASSEMBLY SOCKET
ASSEMBLY
CELL
BRACKET
OLD STYLE
NEW STYLE
Rotate Cell Assembly coun-
terclockwise to remove it.
To replace it insert end
through notched opening in
bracket and rotate clock-
wise. NOTE: If bracket is
ever removed from burner,
Cell Assembly will not fit if
bracket is reinstalled back-
wards.
TYPE 956 FLAME DETECTORS