Repair Parts List - Lennox EL296UHE Installation Instructions Manual

Applications Using A Single-Stage Thermostat
B - Heating Sequence -- Integrated Control Thermostat
Selection DIP Switch 1 ON in "Single-Stage" Position
NOTE - In these applications, two-stage heat will be initi­
ated by the integrated control if heating demand has not
been satisfied after the field adjustable period (7 or 12 min­
utes).
1 - On a call for heat, thermostat first-stage contacts close
sending a signal to the integrated control. The inte­
grated control runs a self‐diagnostic program and
checks high temperature limit switches for normally
closed contacts and pressure switches for normally
open contacts. The combustion air inducer is ener­
gized at low speed.
2 - Once the control receives a signal that the low pres­
sure switch has closed, the combustion air inducer be­
gins a 15-second pre-purge in low speed.
NOTE - If the low fire pressure switch does not close
the combustion air inducer will switch to high fire. After
a 15 second pre-purge the high fire pressure switch
will close and the unit will begin operation on high fire.
After 10 to 20 seconds of high fire operation the unit
will switch to low fire.
3 - After the pre-purge is complete, a 20-second initial ig­
nitor warm-up period begins. The combustion air in­
ducer continues to operate at low speed.
4 - After the 20-second warm-up period has ended, the gas
valve is energized on low fire (first stage) and ignition oc­
curs. At the same time, the control module sends a sig­
nal to begin an indoor blower 30-second ON-delay.
When the delay ends, the indoor blower motor is ener­
gized on the low fire heating speed and the HUM con­
tacts are energized. The integrated control also initi­
ates a second-stage on delay (factory-set at 7
minutes; adjustable to 12 minutes).
5 - If the heating demand continues beyond the second-
stage on delay, the integrated control energizes the
combustion air inducer at high speed. The control also
checks the high fire (second stage) pressure switch to
make sure it is closed. The high fire (second stage)
gas valve is energized and the indoor blower motor is
energized for operation at the high fire heating speed.
6 - When the thermostat heating demand is satisfied, the
combustion air inducer begins a 5-second low speed
post-purge. The field-selected indoor blower off delay
begins. The indoor blower operates at the low-fire
heating speed.
7 - When the combustion air post-purge period is com­
plete, the inducer, the HUM contacts as well as the
120V ACC terminals are de-energized. The indoor
blower is de-energized at the end of the off delay.

Repair Parts List

The following repair parts are available through Lennox
dealers. When ordering parts, include the complete fur­
nace model number listed on the CSA nameplate -- Exam­
ple: EL296UH045XE24B-01. All service must be per­
formed by a licensed professional installer (or
equivalent), service agency, or gas supplier.
Cabinet Parts
Outer access panel
Blower access panel
Top Cap
Control Panel Parts
Transformer
Integrated control board
Door interlock switch
Blower Parts
Blower wheel
Motor
Motor mounting frame
Motor capacitor
Blower housing cutoff plate
Heating Parts
Flame Sensor
Heat exchanger assembly
Gas manifold
Combustion air inducer
Gas valve
Main burner cluster
Main burner orifices
Pressure switch
Ignitor
Primary limit control
Flame rollout switches
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