2nd Ave. Honeywell Relay Modules 7800 Series - Manual (Page 9)

7800 SERIES RELAY MODULES
9 65-0229—1
Table 2. Keyboard Display Module Sequence and Status Hold Messages (continued).
Sequence Status
If the relay module is in a PURGE HOLD status, the following conditions could exist (continued):
PURGE HOLD: T18
(Low Fire Switch
Jumpered) The KDM indicates the burner status and that the Low Fire Switch is jumpered. The Low Fire
Switch is bypassed, welded or otherwise prematurely closed. The system automatically adds 30
seconds to allow the firing rate motor additional drive time to reach or near the closed damper
position before starting the ignition sequence.
PURGE HOLD: F/G
(Flame Detected) The KDM indicates the burner status and that a flame is detected. The burner sequence does not
advance through PREPURGE because a flame is detected as being present. The sequence holds
waiting for the flame signal to clear. If the time exceeds 30 seconds, the relay module locks out.
PURGE HOLD: T18
(Low Fire Switch) The KDM indicates the burner status and that the Low Fire Switch is not closed. The firing rate
motor is driving to its Low Fire position in preparation for Ignition Trials. If this time exceeds four
minutes and fifteen seconds, the relay module locks out.
PURGE HOLD: T7
(Running Interlock) The KDM indicates the burner status and that the Running Interlock is not closed. The sequence
does not advance to ignition until the Running Interlock proves closed. If this time exceeds 30
seconds, the relay module locks out.
PILOT IGN mm:ss The KDM indicates the burner status, PILOT IGN, and the timing of the PILOT IGN trial begins, in
seconds. During this period, the relay module permits the pilot valve to open and the pilot flame
to establish.
If the relay module is in a PILOT HOLD status, the following condition could exist:
PILOT HOLD: TEST
(Run/Test Switch) The KDM indicates the burner status, PILOT IGN, and that the Run/Test Switch is in the TEST
position. The sequence does not continue until the Run/Test Switch is placed in the RUN
position.
MAIN IGN mm:ss The KDM indicates the burner status, MAIN IGN, and the timing of the MAIN IGN trial begins, in
seconds. During this period, the relay module permits the main valve to open and the main flame
to establish.
RUN The KDM indicates the burner status, RUN, which is the period of time after the Ignition Trials and
before the operating controller setpoint is reached. During this time, the burner is firing under
control of the firing rate control.
If the relay module is in a RUN HOLD status, the following condition could exist:
RUN LOWFIRE: TEST
(Run/Test Switch) The KDM indicates the burner status and that the Run/Test Switch is in the TEST position.
Normal modulation or operation does not continue until the Run/Test Switch is placed in the RUN
position.
POSTPURGE mm:ss The KDM indicates the burner status, POSTPURGE, which is the period of time after the RUN
period when the blower motor continues to run. The timing of the POSTPURGE period is fifteen
seconds.
Waiting for
connection... The KDM has power but is waiting to receive a signal from the relay module to continue
operation.
RESET/ALARM TEST The KDM indicates the burner status, RESET/ALARM TEST. This condition indicates that the
reset button is pressed. If it is held for more than four seconds, the alarm output is energized. The
alarm output is de-energized when the reset button is released.
Additional Sequence Status Information When An Expanded Annunciator Is Connected To The Relay Module:
BURNER OFF: T6
(Burner Switch) The KDM indicates the Burner Switch is not closed. The burner sequence does not advance to
PREPURGE until the Burner Switch closes.
STANDBY The KDM indicates the burner status, STANDBY, and that the Operating Control is not closed.
The burner sequence does not advance to PREPURGE until the Operating Control closes.
STANDBY HOLD: T6
(EA Hold Message) The KDM indicates the burner status, STANDBY, and that a limit is not closed. The burner
sequence does not advance to PREPURGE until one or all limits close downstream from the
Operating Control.
STANDBY HOLD: T6
(Circuit Fault) The KDM indicates the burner status, STANDBY, and that the control input is not closed. The
burner sequence does not advance to PREPURGE until the control input closes.
NOTE: Normal sequences are in bold type, while abnormal sequences are in regular type. This table is for all 7800 SERIES
Relay Modules so all listed steps may not apply to the unit installed.