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www.DaikinApplied.com 15
OM 1077-1 • MAVERICK I
Ignition Retry
If flame is not established on the first trial for ignition period,
the induced draft motor remains energized and the IFC
deenergizes the low gas valve. The IFC waits for a 60 second
inter-purge period then attempts an ignition re-try. If the second
ignition trial is unsuccessful, the IFC energizes the high inducer
and waits indefinitely for the high pressure switch to close.
When the high pressure switch closes, the IFC energizes the
high gas output, interpurges 60 seconds and tries the 3rd and
4th ignition attempts on high fire.
If flame is not established on the fourth trial for ignition, the
IFC de-energizes the high and low gas outputs and goes into
lockout. The IFC indicates a fault by flashing the status LED 1
time to indicate lockout is due to failed ignition.
Ignition Recycle
If flame is established and maintained during the trial for
ignition period and then flame is lost, the gas valve is
deenergized, the induced draft motor continues to run, and the
control begins timing the pre-purge delay. The indoor blower
motor will be energized and/or remain energized on heat speed
for the delay OFF time.
When the pre-purge delay is over, the control energizes
the spark and gas valve for an ignition attempt. If ignition is
unsuccessful, the IFC will attempt up to 3 more retries as
described above. The IFC will recycle up to 17 flame losses
(16 recycles) within a single call for heat before going to
lockout. The IFC status LED will flash 1 time if lockout is due
to too many flame loses. (This is same flash code as failed
ignition.).
Open Limit switch
The limit switch is ignored unless a call for heat is present.
If the limit switch opens while a call for heat is present, the
indoor fan is energized on heat speed and both inducers are
energized. The gas valve is de-energized if it was energized.
The status LED will flash 3 times indicating the Limit switch is
open. The blower and inducers will remain energized as long
as the limit is open and there is a call for heat.
If the call for heat goes away while the limit switch is open, the
induced draft motor will run through post purge and the indoor
blower will run through the heat fan off delay. The status LED
will return to steady on.
If the limit switch re-closes and the call for heat remains, the
status LED will return to steady on and the IFC will begin a pre-
purge time with high gas output energized to begin a re-ignition
attempt. The indoor blower remains on (for the delay OFF time)
through the re-ignition attempt.
Open Rollout switch
The rollout switch is ignored unless a call for heat is present
and the limit switch is closed. If the rollout switch opens for
more than 1 second, the indoor fan is energized on heat speed
for a heat blower OFF delay period and the inducer motor is
energized for a post-purge time period. The gas valve is de-
energized if it was energized. The status LED will flash 5 times
indicating the rollout switch is open and the IFC is in lockout.
If the rollout switch re-closes before the call for heat goes away,
the IFC will remain in lockout with the LED flashes 5 times.
NOTE:
Rollout switch open for less than 1 second will cause
interrupted heat cycle from open PS, however it will
not lock out.
Pressure switch
The pressure switches are ignored unless a call for heat is
present and the limit and rollout switches are closed. When a
call for heat occurs and either pressure switch is closed before
the inducer is energized, the inducer will remain OFF and the
LED will flash 2 times until both pressure switches open.
If either pressure switch opens before the ignition period, both
induced draft motor will remain ON, the high gas output will
be de-energized, and the LED will flash 2 times. When both
pressure switches are closed, the LED flash code is cleared,
the high gas output is energized, and the control re-starts the
prepurge period.
If the low pressure switch opens after the gas valve has been
energized, the control will de-energize both gas outputs and
run the indoor blower on heat speed through the fan OFF
delay. The low inducer remains energized and the high inducer
energizes if it was not already energized. When both pressure
switches re-close, the control begins the pre-purge period and
re-ignites. If the call for heat goes away before the pressure
switches close, both inducer motors are de-energized and the
control goes to standby.
If the high pressure switch opens while in high heat and the low
pressure switch remains closed, the control de-energizes the
high gas output and attempts to reestablish high heat.
Call for Fan
When the DDC Controller calls for continuous fan (Cont Fan)
without a call for heat, the indoor fan is immediately energized.
The fan remains energized as long as the call for fan remains
without a call for heat.
The continuous fan operation continues to function while the
control is in heat mode lockout.
