Lennox G32 SERIES, Информация об устройстве

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Page 37
Sequence of Operation G32−2, −3
Ignitor operation will vary between SureLight boards.
Boards 24L85, 56L83 and 63K89, will energize ignitor for
the first second of the 4 second ignition trial. Board 97L48
will energize ignitor during the trial until flame is sensed.
1 − When there is a call for heat, W1 of the thermostat en
ergizes W of the furnace control with 24VAC.
2 − SureLight control runs self−check for S10 primary limit
switch normally closed contacts. The control also
checks S128 combustion air prove switch and S102
high fire pressure switch normally open contacts. Fol
low steps 4 through 8 per respective thermostat.
Single−stage Mode, Single−stage Thermostat
3 − SureLight control energizes combustion air blower B6
on high speed. Combustion air blower runs until S102
high fire pressure switch closes (switch will close with
in 2−1/2 minutes or control goes into Watchguard−
Pressure Switch mode). A 15−second pre−purge fol
lows after S102 closes.
4 − SureLight control energizes ignitor. A 20−second
warm−up period begins.
5 − Gas valve is energized on first stage heat (low). Gas
valve opens for a 4 second trial for ignition.
6 − Flame is sensed. After 8 seconds from when gas valve
opens, valve energizes on second stage (high heat).
7 − After 45−second delay, indoor blower B3 is energized
on heating speed.
Two−stage Mode, Single−stage Thermostat
1 − SureLight control energizes combustion air blower B6
on low speed. Combustion air blower runs until com
bustion air blower switch S102(or S128 onG32−75
units) closes (switch will close within 2−1/2 minutes or
control goes into Watchguard−Pressure Switch
mode). A 15−second pre−purge follows once S102
closes.
2 − SureLight control energizes ignitor. A 20−second
warm−up period begins.
3 − Gas valve is energized on first stage. Gas valve opens
for a 4−second trial for ignition. Signal is sent from con
trol module to two−stage control board to begin W2
(second−stage) ON delay.
4 − Flame is sensed, gas valve remains open for the heat
call.
5 − After 45−second delay, indoor blower B3 is energized
on low speed.
6 − Second stage time on delay complete (8, 12, or 15
minutes). Combustion air blower B6 switches to high
speed, indoor blower B3 switches to heating speed
and gas valve opens on high fire (second stage.)
Two−stage Mode, Two−stage Thermostat
1 − SureLight control energizes combustion air blower B6
on low speed. Combustion air blower runs until com
bustion air blower switch S102 closes (or S128 on
G3275 units. Switch will close within 2−1/2 minutes or
control goes into Watchguard−Pressure Switch
mode). A 15−second pre−purge follows once S102
closes.
2 − SureLight control energizes ignitor. A 20−second
warm−up period begins.
3 − Gas valve is energized on first stage only. Gas valve
opens for a 4−second trial for ignition.
4 − Flame is sensed, gas valve remains open for the heat
call.
5 − After 45−second delay, indoor blower B3 is energized
on low speed.
6 − Call for second stage heat comes from indoor thermo
stat (W2).