30
RM795A,B,C,D
TROUBLESHOOTING
(continued)
TABLE 6—SEQUENCE AND STATUS HOLD MESSAGES (Continued)
NOTE: Normal sequences are in bold type, while abnormal sequences are not in bold type.
Sequence
Status
STANDBY
The LED indicates the burner status, POWER. The burner can be
placed in STANDBY by opening the burner switch or if the operating
controller indicates its set point has been satisfied. If a demand is
present for burner operation, the burner sequence will not advance
from STANDBY to PURGE until the recycle limits close.
If the RM7895 is in a HOLD status, the following conditions could exist:
STANDBY HOLD: F/G (Flame Detected)
The LEDs indicate the burner status, POWER and FLAME, and
that a flame is detected. A demand is present for burner operation.
The burner sequence will not advance to PREPURGE because a
flame is detected as being present. The sequence will not advance
to PREPURGE until the flame signal clears. If the flame signal does
not clear within 40 seconds, the RM7895 will lockout.
STANDBY HOLD: T7 (Airflow Interlock)
The LED indicates the burner status, POWER, and that the Air-flow
Interlock is closed. A demand is present for burner operation and
the burner sequence will not advance to PREPURGE until the
Airflow Interlock proves open. If this time exceeds the 120 second
hold, the RM7895B,D will lockout.
PURGE
The LED indicates the burner status, POWER, and that it is the
period of time before ignition during which time the blower motor
is running. The timing of the PURGE period is selectable.
If the RM7895 is in a HOLD condition, the following conditions could exist:
PURGE HOLD: TEST (Run/Test Switch)
The LED indicates the burner status, POWER, and that the Run/Test
Switch is in the TEST position. The sequence will not continue until
the Run/Test Switch is placed in the RUN position (RM7895C,D).
PURGE HOLD: F/G (Flame Detected)
The LEDs indicate the burner status, POWER and FLAME, and
that a flame is detected. The burner sequence will not advance
through PREPURGE because a flame is detected as being present.
The sequence will hold waiting for the flame signal to clear. If the
time exceeds 30 seconds, the RM7895 will lockout.
PURGE HOLD: T7 (Airflow Interlock)
The LED indicates the burner status, POWER, and that the Air-
flow Interlock is not closed. The sequence will not advance to
ignition until the Airflow Interlock proves closed. If this time exceeds
a 30 second HOLD, the RM7895 will lockout.
PILOT IGN
The LEDs indicate the burner status, POWER, PILOT and
FLAME, which is the period of time the RM7895 permits the pilot
valve to be open and the pilot flame to be established.
If the RM7895 is in a HOLD status, the following condition could exist:
PILOT HOLD: TEST (Run/Test Switch)
The LEDs indicate the burner status, POWER, PILOT and
FLAME, and that the Run/Test Switch is in the TEST position. The
sequence will not continue until the Run/Test Switch is placed in
the RUN position (RM7895C,D).
MAIN IGN
The LEDs indicate the burner status, POWER, PILOT, FLAME
and MAIN, which is the period of time the RM7895 permits the
main valve to be open and the main flame to be established.
RUN
The LEDs indicate the burner status, POWER, PILOT, FLAME
and MAIN, which is the period of time after the Ignition Trials and
before the operating controller set point is reached. During this
time, the burner is firing under the control of the operating control-
ler (RM7895A,B).
