INSTALLATION INSTRUCTIONS
69-2088-01
®
Automatic Ignition Systems
ANSI Z21.20
S9240F1004 Modulating Hot Surface
Ignition Integrated Furnace Control
APPLICATION
The S9240F1004 Integrated Furnace Control (IFC) is
designed specifically to work with a Lennox G71MPP variable
firing rate, high efficiency furnace. It provides gas ignition,
safety shutoff, and variable speed fan control with multi-firing
rate gas heating and up to 2-stage electric cooling
applications.
FEATURES
The S9240F1004 provides the following features:
• Monitors a single stage or 2-stage conventional low
voltage thermostat for requests for heat, cool, or fan.
• Monitors an input provided for connection to a
thermostat with a dehumidification output or Harmony
III Zone Control.
• Provides three stage furnace input rate control when
operating with a conventional single stage thermostat.
• Provides 2-stage or modulating furnace input rate
control based on field selected option when operating
with a conventional 2-stage thermostat.
• Manages ignition of a main burner flame up to 400,000
BTU per hour using a 95 V hot surface igniter.
• Monitors the appliance pressure, limit, and rollout
switches and generate control actions as
programmed.
• Controls the 24 Vac Honeywell amplified gas/air gas
valve.
• Controls a 3-phase 120 Vac inducer motor (Fasco
Model 92B1 or other with identical voltage/frequency
curve) and blower assembly based on heat demand
and other parameters.
• Controls the Regal Beloit 3.0 ECM circulator motor and
blower based on defined appliance CFM profiles
and/or a discharge air sensor signal.
• Controls single stage or 2-stage cooling equipment.
The outdoor unit is controlled directly by the 24 Vac
conventional thermostat inputs. The IFC manages the
circulator speed based on cool demand and other
parameters.
• Controls a 120 Vac humidifier output and a 120 Vac
EAC output.
• Operates with 120 Vac single phase, 60 Hz power
supply.
• Uses a 7-segment LED display to communicate error
code and status information. A single on board button
is provided to generate the desired information
display.
• Provides field selectable DIP switches to select field
specific control operating parameters such as type of
thermostat, delay timings, and fan operating
parameters.
• Provides on-board jumpers that can be clipped to
permanently enable 2-stage cooling, heat pump
compatibility, dehumidification sequences, and define
appliance characteristics for field replacement
purposes.
• Provides Field Test Mode and Diagnostic Recall Mode
to assist the installation/service technician.
• Stores the 10 most recent error codes, which are
accessible by the service technician in Diagnostic
Recall Mode.