35
■
Furnace fails to
operate.
■
Integrated
control module
LED display
provides “EA”
error code.
EA
■
Polarity of
115-volt AC is
reversed.
■
Polarity of 115-volt
AC power to
furnace or
integrated module
is reversed.
■
Poor furnace
ground.
■
Review wiring diagram
to correct polarity.
■
Verify proper ground.
Correct if necessary.
■
Check and correct
wiring.
■
Turn off power prior to
repair.
■
Furnace fails to
operate.
■
Integrated
control module
LED display
provides “d0”
error code.
d0
■
Data not yet on
network.
■
Furnace does not
contain any shared
data.
■
Populate shared data
set using memory
card.
■
Turn off power prior to
repair.
■
Use memory card for
the specific model.
■
Insert memory card
before turning on
power. Memory card
may be removed after
data is loaded.
■
Turn off power before
removing memory
card.
■
Error code will be
cleared once data is
loaded.
■
Operation
different than
expected or no
operation.
■
Integrated
control module
LED display
provides “d4”
error code.
d4
■
Invalid memory
card data.
■
Shared data set on
memory card has
been rejected by
integrated control
module.
■
Verify shared data set
is correct for the
specific model.
■
Repopulate data using
correct memory card, if
required.
■
Turn off power prior to
repair.
■
Use memory card for
the specific model.
■
Insert memory card
before turning on
power. Memory card
may be removed after
data is loaded.
■
Turn off power before
removing memory
card.
■
Error code will be
cleared once data is
loaded.
■
Furnace fails to
operate.
■
Integrated
control module
LED display
provides “b0”
error code.
b0
■
Circulator
blower motor is
not running
when it should
be running.
■
Loose wiring
connection at
circulator motor
power leads or
circulator motor
power leads
disconnected.
■
Open circuit in
inductor or loose
wiring connection
at inductor (
³⁄₄
Hp
and 1 Hp models
only).
■
Failed circulator
blower motor.
■
Tighten or correct
wiring connection.
■
Verify continuous
circuit through
inductor. Replace if
open or short circuit.
■
Check circulator
blower motor. Replace
if necessary
■
Turn off power prior to
repair.
■
Replace inductor with
correct replacement
part.
■
Replace circulator
motor with correct
replacement part.
Symptoms of
Abnormal
Operation
Diagnostic/
Staus LED
Code
Fault Description Possible Causes
Corrective Actions
Notes and Cautions