Specifications

Page 16
COMBUSTION AIR BLOWER
COMBUSTION AIR
BLOWER CAPACITOR C3
COMBUSTION AIR
BLOWER MOTOR B6
GAS VALVE
GAS MANIFOLD
HEATING CONTROLS BOX
OR
CONTROLS HAT SECTION
SPARK ELECTRODE
(hidden from view)
FLAME SENSOR
ELECTRODE
HEAT EXCHANGER
TUBES
BURNERS
AIR BAFFLE
PROVE SWITCH S18
(outer portion of motor housing)
FIGURE 12
FLAME ROLLOUT
SWITCH S47
ROLLOUT SWITCH
MOUNTING BRACKET
TYPICAL HEAT EXCHANGER ASSEMBLY
GCS24-1353, -1603
HEATING CONTROL COMPONENTS
FIGURE 13
K20
DL3
K25
A3
BLOWER DELAY
RELAY K25
2ND STAGE GAS
HEAT DELAY DL3
INDOOR BLOWER
(LIMIT) RELAY K20
BURNER IGNITION
CONTROL A3
IX-GAS HEAT
A-Heating Control Box Components
(Figure 13)
1-Indoor Blower (Limit) Relay K20
Relay K20 is a DPDT relay located in the heating control box.
Relay K20 is energized when either the primary or secondary
high temperature limits trip. When K201 is energized, a set of
N.O. contacts close to energize relay K3 in the unit. Relay K3
energizes the indoor blower for safety cooldown. When
K202 is energized, a set of N.C. contacts open to deener
gize GV1. When either the primary or secondary limit are re
set normal operation is resumed.
2-2nd Stage Gas Heat Delay DL3
DL3 is a SPST time delay located in the heating control box.
Upon receiving increased heating demand from W2, DL3 initi
ates a 180 second time delay before closing its N.O. contacts.
DL3 prevents frequent cycling of 2nd stage heat. When DL3
contacts close, 2nd stage operation begins. When 2nd stage
heating demand stops time delay DL3 is de-energized and re
set immediately. When DL3 resets, the 2nd stage operator of
the gas valve is de-energized and closed.
3-Blower Delay Relay K25
A heat type combination blower delay / relay (K25) located in
the heating controls box coordinates blower operation with
burner operation. K25 is a SPDT relay which closes 40+10
seconds after being energized and opens 110+20 seconds
after being de-energized.
4-Burner Ignition Controls A3
All models use direct spark, multiple try ignition. Units are
equipped with a single ignition control, spark and flame sen
sor (A3).