Unit Components Upflow Q" Units; Unit Components Horizontal/Reverse Flow V" Units - Lennox G21Q3-40 Unit Information

DIFFERENTIAL PRESSURE
IGNITION CONTROL
AIR FLAPPER VALVE
INSULATION
SPARK PLUG & SENSOR ACCESS
PANEL
TERMINAL STRIP
EXHAUST OUTLET

UNIT COMPONENTS HORIZONTAL/REVERSE FLOW V" UNITS

SPARK PLUG
& SENSOR ACCESS
PANEL
HEATING
COMPARTMENT
INSULATION
AIR FLAPPER
VALVE
GAS FLAPPER VALVE
& ORIFICE ASSEMBLY
MODULATION/LIMIT
CONTROL

UNIT COMPONENTS UPFLOW Q" UNITS

LIMIT CONTROL
SWITCH
TB1
BLOWER
(ICM2 SHOWN WITH VSP2−1)
IGNITION
CONTROL
PURGE BLOWER
EXPANSION
GAS VALVE
TANK
Page 11
AIR INTAKE PVC CONNECTION
GAS VALVE
EXPANSION TANK
GAS FLAPPER VALVE
& ORIFICE ASSEMBLY
HEATING COMPARTMENT
CONTROL BOX
DOOR INTERLOCK SAFETY SWITCH
AIR INTAKE PVC CONNECTION
DIFFERENTIAL PRESSURE
SWITCH
TERMINAL STRIP TB1
DOOR INTERLOCK
CONTROL
EXHAUST
BOX
OUTLET
PURGE BLOWER
VSP2 1
CONTROL BOARD
BLOWER
SAFETY SWITCH