S9200U Installation Guide

S9200U1000 UNIVERSAL HOT SURFACE IGNITION INTEGRATED FURNACE CONTROL
69-2075EF—05 14
— A maximum of three recycles are allowed on a
single call for heat before the control proceeds
to Soft Lockout. The recycle count is not
cleared until the current demand for heat is
satisfied or the S9200U1000 has just exited
Soft Lockout or the S9200U1000 is in run
mode continuously for one hour.
Rollout Circuit Operation (during Heat
cycle)
If the rollout circuit opens during a heating cycle:
— The gas valve is immediately de-energized.
— The inducer is energized.
—The circulator is energized at heat speed.
— An LED error code is flashed, which indicates
the rollout circuit has opened. See Table 12 on
page 21.
— An EnviraCOM™ alarm is active and sent on the
bus. See Table 14 on page 23.
— Thermostat requests for heat are ignored.
The S9200U1000 remains in this state until the
rollout circuit closes.
Once the rollout circuit has closed:
— The inducer is de-energized after the Post-
purge Period.
— The circulator is de-energized after the
selected heat off delay.
— The LED continues to flash the rollout switch
error code.
— Thermostat requests for heat are still ignored.
The S9200U1000 remains in this state until power is
cycled, at which time the S9200U1000 resumes
normal operation.
Limit Switch Circuit Operation (during
Heat cycle)
If the limit circuit opens during a heating cycle:
— The gas valve is immediately de-energized and
the inducer is de-energized after the Postpurge
Period.
— The LED flashes an error code, indicating the
limit circuit is open. See Table 12 on page 21.
— An EnviraCOM™ alarm is active and sent on the
bus. See Table 14 on page 23.
— The circulator is immediately energized or
remains energized at the heat speed.
— If the limit switch opens during the Trial for
Ignition period, the trial is treated as a failed
one (next trial is retry).
— If the limit switch opens in run mode, the
sequence is treated as a failed one (next trial is
recycle).
The S9200U1000 remains in this state until the limit
circuit closes. Once the limit circuit closes:
— If the limit circuit was open for less than three
minutes, a new ignition sequence is started
and the circulator will remain energized for the
selected fan off delay. If the burner is lit before
expiration of the selected fan off delay, the fan
off timing is stopped and the circulator
remains energized.
— If the limit circuit was open for longer than
three minutes, the circulator will remain ener-
gized at heat speed for the selected heat fan off
delay, and the S9200U1000 will proceed to
Soft Lockout, where it will remain for the Auto
Restart Delay or until a thermostat reset is
detected.
Pressure Switch Operation (during
Heat cycle)
— If a call for heat is initiated and the pressure
switch is closed before the ignition sequence
has begun, the S9200U1000 will wait five sec-
onds and flash an LED error code, which indi-
cates the pressure switch is stuck closed. An
EnviraCOM™ alarm is active and sent on the
bus (see Table 14 on page 23). As soon as the
pressure switch opens the error code clears
and the ignition sequence proceeds as normal.
— If the ignition sequence has begun and the
pressure switch fails to close within 150 sec-
onds of energizing the inducer, the
S9200U1000 de-energizes the inducer, starts
flashing the “Pressure Switch Failed Open”
error code and returns to Idle Mode for five
minutes before beginning the ignition
sequence again (see Table 12 on page 21). An
EnviraCOM™ alarm is active and sent on the
bus (see Table 14 on page 23).
— This process continues indefinitely and an
error code indicating a failed pressure switch
flashes until the pressure switch finally closes
or the call for heat ends.
— If the pressure switch opens during Prepurge
or Igniter Warm-up, the S9200U1000 will de-
energize the igniter and leave the inducer ener-
gized for a maximum of 60 seconds to try and
re-close the switch. If the switch closes, the
ignition cycle will resume from the beginning
of Prepurge again. If the switch does not re-
close, the S9200U1000 behaves as if the pres-
sure switch had not closed after the inducer
turned on.
— If the pressure switch opens for longer than
two seconds during Trial for Ignition or opens
for longer than 50 milliseconds during normal
fire operation and flame is lost, the
S9200U1000 proceeds to Interpurge before
attempting the ignition sequence again.
An error code indicating the pressure switch
failed open flashes until the burner is lit again
or the heat demand is removed (see Table 12
on page 21). An EnviraCOM™ alarm is active
and sent on the bus (see Table 14 on page 23.)
— If the pressure switch opens for longer than
two seconds during Interpurge, the
S9200U1000 proceeds to the “Wait for Pres-
sure Switch to Close” state.
Hot Surface Igniter (HSI) Control
The Hot Surface Igniter is directly powered by line
voltage input. The HSI warm-up time is shorter for the
first ignition trial when using the 17/27 second warm-
up time setting and longer for subsequent trials. See
Table 10 on page 12.
Normal Cooling Mode
A call for cooling is signaled by:
— The shorting of R/2 to Y.
— The shorting of R/2 to Y and G simultaneously.
— An EnviraCOM™ cool demand of any stage.
Refer to Fig. 10 on page 19 for the control sequence
diagram.