GMS8 Installation Manual
32
T
ROUBLESHOOTING
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
NOTE: Discharge body’s static electricity before touching unit. An
electrostatic discharge can adversely affect electrical components.
Use the following precautions during furnace installation and ser-
vicing to protect the integrated control module from damage. By
putting the furnace, the control, and the person at the same elec-
trostatic potential, these steps will help avoid exposing the inte-
grated control module to electrostatic discharge. This procedure
is applicable to both installed and uninstalled (ungrounded) fur-
naces.
1. Disconnect all power to the furnace. Do not touch the
integrated control module or any wire connected to the
control prior to discharging your body’s electrostatic
charge to ground.
2. Firmly touch a clean, unpainted, metal surface of the
furnace away from the control. Any tools held in a person’s
hand during grounding will be discharged.
3. Service integrated control module or connecting wiring
following the discharge process in step 2. Use caution not
to recharge your body with static electricity; (i.e., do not
move or shuffle your feet, do not touch ungrounded objects,
etc.). If you come in contact with an ungrounded object,
repeat step 2 before touching control or wires.
4. Discharge your body to ground before removing a new
control from its container. Follow steps 1 through 3 if
installing the control on a furnace. Return any old or new
controls to their containers before touching any ungrounded
object.
DIAGNOSTIC CHART
Refer to the troubleshooting chart in the Appendix for assistance
in determining the source of unit operational problems. The red
diagnostic LED blinks to assist in troubleshooting the unit. The
number of blinks refer to a specific code.
NOTE: To clear all alarm codes, depress the push button for 6
seconds.
FAULT RECALL
(FURNACES EQUIPPED W ITH PCBBF132 CONTROL BOARD ONLY)
The ignition control is equipped with a momentary push button
switch that can be used to display on the diagnostic LED the last
five faults detected by the control. The control must be in Standby
M ode (no thermostat inputs) to use the feature. Depress the
pushbutton switch for approximately 2 seconds. Release the
switch when the LED is turned off. The diagnostic LED will then
display the flash codes associated with the last five detected faults.
The order of display is the most recent fault to the least recent
fault.
RESETTING FROM LOCKOUT
Furnace lockout results when a furnace is unable to achieve igni-
tion after three attempts. It is characterized by a non-functioning
furnace and a one flash diagnostic LED code from the red LED. If
the furnace is in “lockout”, it will (or can be) reset in any of the
following ways.
1. Automatic reset. The integrated control module will
automatically reset itself and attempt to resume normal
operations following a one hour lockout period.
2. M anual power interruption. Interrupt 115 volt power to
the furnace for 1 - 20 seconds.
3. M anual thermostat cycle. Lower the thermostat so that
there is no longer a call for heat for 1 - 20 seconds then
reset to previous setting.
NOTE: If the condition which originally caused the lockout still
exists, the control will return to lockout. Refer to the Diagnostic
Chart for aid in determining the cause.
M
AINTENANCE
T
O
AVOID
ELECTRICAL
SHOCK
,
INJURY
OR
DEATH
,
DISCONNECT
ELECTRICAL
POW ER
BEFORE
PERFORM ING
ANY
M AINTENANCE
. I
F
YOU
M UST
HANDLE
THE
IGNITER
,
HANDLE
W ITH
CARE
. T
OUCHING
THE
IGNITER
ELEM ENT
W ITH
BARE
FINGERS
,
ROU GH
HANDLING
,
OR
VIBRATION
COULD
DAM AGE
THE
IGNITER
RESULTIN G
IN
PREM ATURE
FAILURE
. O
NLY
A
QUALIFIED
SERVICER
SHOULD
EVER
HANDLE
THE
IGNITER
.
WARNING
ANNUAL INSPECTION
The furnace should be inspected by a qualified installer, or ser-
vice agency at least once per year. This check should be performed
at the beginning of the heating season. This will ensure that all
furnace components are in proper working order and that the
heating system functions appropriately. Pay particular attention
to the following items. Repair or service as necessary.
• Flue pipe system. Check for blockage and/ or leakage.
Check the outside termination and the connections at
and internal to the furnace.
• Heat exchanger. Check for corrosion and/ or buildup
within the heat exchanger passageways.
• Burners. Check for proper ignition, burner flame, and
flame sense.
• Wiring. Check electrical connections for tightness and/
or corrosion. Check wires for damage.
• Filters.
FILTERS
T
O
AVOID
PROPERTY
DAM AGE
,
PERSONAL
INJURY
OR
DEATH
,
DISCONNECT
ELECTRICAL
POW ER
BEFORE
REM OVING
FILTERS
. N
EVER
OPERATE
FURNACE
W ITHOUT
A
FILTER
INSTALLED
BECAUSE
DUST
AND
LINT
W ILL
BUILD
UP
ON
INTERNAL
PARTS
RESULTIN G
IN
LOSS
OF
EFFICIENCY
,
EQUIPM ENT
DAM AGE
AND
POSSIBLE
FIRE
.
WARNING