Roubleshooting, Hart – Goodman Mfg GHS8 User Manual

Page 29

Advertising
background image

29

IO-242C

05/05

1

Integrated control module will automatically attempt to reset from lockout after one hour.

2

LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.

T

ROUBLESHOOTING

C

HART

• Furnace lockout due

to an excessive
number of ignition
attempt (1 total) and
“retries” (3 total)

1

.

• Auxiliary Limit Open

• Locate and correct

gas interruption.

• Replace or realign

igniter.

• Check flame sense

signal. Sand sensor if
coated and/or
oxidized.

• Check flue piping for

blockage, proper
length, elbows, and
termination.

• Verify proper induced

draft blower
performance.

• Check circulator

blower speed and
performance. Correct
speed or replace
blower if necessary.

• Turn power OFF

prior to repair.

• Igniter is fragile,

handle with care.

• Clean flame

sensor with steel
wool.

• See “Combustion

and Ventilation Air
Requirements” and
“Category I
Venting (Vertical
Venting)” section
for details.

• See Product Data

Bulletin for
allowable rise
range and proper
circulator speed.

• Furnace fails to operate.

• Integrated control

module diagnostic LED
is flashing ONE (1)
flash.

1

1 FLASH

• Failure to establish flame.

Cause may be no gas to
burners, bad igniter or
igniter alignment,
improper orifices, or
coated/oxidized or
improperly connected
flame sensor.

• Loss of flame after

establishment. Cause may
be interrupted gas supply,
lazy burner flames
(improper gas pressure or
restriction in flue or
improper induced draft
blower performance.

• Insufficient conditioned air

over the heat exchanger.
Blocked filters, restrictive
ductwork, improper
circulator blower speed, or
failed circulator blower.

• Pressure switch

circuit is closed.

• Induced draft blower

is not operating.

• Replace induced draft

blower pressure
switch.

• Repair short.

• Turn power OFF

prior to repair.

• Replace pressure

switch with proper
replacement part.

• Furnace fails to operate.

• Integrated control

module diagnostic LED
is flashing TWO (2)
flashes.

2

2 FLASHES

• Induced draft blower

pressure switch contacts
sticking.

• Shorts in pressure switch

circuit.

• Inspect pressure

switch hose. Repair, if
necessary,

• Inspect flue for

blockage, proper
length, elbows, and
termination.

• Correct pressure

switch setpoint or
contact motion.

• Tighten or correct

wiring connection.

• Pressure switch hose

blocked, pinched or
connected improperly.

• Blocked flue or weak

induced draft blower.

• Incorrect pressure switch

setpoint or malfunctioning
switch contacts.

• Loose or improperly

connected wiring.

• Pressure switch

circuit not closed.

• Induced draft blower

is operating.

• Induced draft blower

runs continuously with
no further furnace
operation.

• Integrated control

module diagnostic LED
is flashing THREE (3)
flashes.

3

3 FLASHES

• Turn power OFF

prior to repair.

• See “Combustion

and Ventilation
Air
Requirements”
and “Category I
Venting (Vertical
Venting)” section
for details.

• Replace pressure

switch with proper
replacement part.

• Integrated control

module has an
internal fault.

• Integrated control module

has an internal fault.

• Replace bad integrated

control module.

• Turn power OFF

prior to repair.

• Read precautions

in “Electrostatic
Discharge” section
of manual.

• Furnace fails to operate.

• No 115 volt power

to furnace, or no 24
volt power to
integrated control
module.

• Blown fuse or circuit

breaker.

• Manual disconnect switch

OFF, door switch open, or
24 volt wires improperly
connected or loose.

• Blown fuse or circuit

breaker.

• Assure 115 and 24 volt

power to furnace
integrated control
module.

• Check integrated control

module fuse (3A).
Replace if necessary.

• Check for possible shorts

in 115 and 24 volt
circuits. Repair as
necessary.

• Turn power OFF

prior to repair.

• Replace integrated

control module
fuse with 3A
automotive fuse.

• Furnace fails to operate.

• Integrated control

module diagnostic LED
provides no signal.

NONE

Fault Description(s)

Possible Causes

Corrective Action

Cautions and Notes

Symptoms of Abnormal

Operation

Associated

LED Code

2

Advertising