Safety Circuit Description; General; Integrated Control Module; Primary Limit - Goodman AKSS9/GKS9 Installation Instructions Manual

Burner Flame
XVII. SAFETY CIRCUIT DESCRIPTION
G
ENERAL
A number of safety circuits are employed to ensure safe and proper
furnace operation. These circuits serve to control any potential safety
hazards and serve as inputs in the monitoring and diagnosis of abnor-
mal function. These circuits are continuously monitored during fur-
nace operation by the integrated control module.
I C M
NTEGRATED ONTROL ODULE
The integrated control module is an electronic device which, if a po-
tential safety concern is detected, the module will take the necessary
precautions and provide diagnostic information through an LED.
P L
RIMARY IMIT
The primary limit control is located on the partition panel and monitors
heat exchanger compartment temperatures. It is a normally-closed
(electrically), automatic reset, temperature-activated sensor. The limit
guards against the overheating as a result of insufficient conditioned
air passing over the heat exchanger.
A L
UXILIARY IMIT
The auxiliary limit control(s) are located on or near the circulator blower
and monitors heat exchanger compartment temperatures. They are
a normally-closed (electrically), manual-reset, temperature activated
sensors. These limits guard against overheating as a result of insuf-
ficient conditioned air passing over the heat exchanger.
R L
OLLOUT IMIT
The rollout limit controls are mounted on the burner/manifold assem-
bly and monitor the burner flame. They are normally-closed (electri-
cally), manual-reset, temperature-activated sensors. These limits
guard against burner flames not being properly drawn into the heat
exchanger.
P S
RESSURE WITCHES
The pressure switches are normally-open (closed during operation),
single-pole single-throw, negative air pressure-activated switches.
They monitor the airflow (combustion air and flue products) through
the heat exchanger via pressure taps located on the induced draft
blower and the coil front cover. These switches guard against insuffi-
cient airflow (combustion air and flue products) through the heat ex-
changer and/or blocked condensate drain conditions.
F S
LAME ENSOR
The flame sensor is a probe mounted to the burner/manifold assem-
bly which uses the principle of flame rectification to determine the pres-
ence or absence of flame.
Check the
Burner Flames for:
1. Stable, soft and blue.
2. Not curling, floating
or lifting off.
XVIII. TROUBLESHOOTING
E D
LECTROSTATIC ISCHARGE
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 servicing
to protect the integrated control module from damage. By putting the
furnace, the control, and the person at the same electrostatic poten-
tial, these steps will help avoid exposing the integrated control module
to electrostatic discharge. This procedure is applicable to both in-
stalled and uninstalled (ungrounded) furnaces.
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 furnaces
near 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.
D C
IAGNOSTIC HART
HIGH VOLTAGE!
T
O AVOID PERSONAL INJURY OR DEATH DUE TO
,
ELECTRICAL SHOCK DISCONNECT ELECTRICAL POWER
P
BEFORE ERFORMAING ANY SERVICE OR MAINTENANCE
Refer to the Troubleshooting Chart at the end of this manual for assis-
tance in determining the source of unit operational problems. The red
diagnostic LED blinks to assist in troubleshooting the unit. The num-
ber of blinks refers to a specific fault code.
R F L
ESETTING ROM OCKOUT
Furnace lockout results when a furnace is unable to achieve ignition
after three attempts during a single call for heat. It is characterized by
a non-functioning furnace and a one flash diagnostic LED code. 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. Manual power interruption. Interrupt 115 volt power to the
furnace for 1 - 20 seconds.
3. Manual thermostat cycle. Lower the thermostat so that there
is no longer a call for heat then reset to previous setting.
Interrupt thermostat signal to the furnace for 1 - 20 seconds.
NOTE: If the condition which originally caused the lockout still exists,
the control will return to lockout. Refer to Section XVIII, Troubleshooting
- Diagnostic Chart for aid in determining the cause.
32
(ESD) P
RECAUTIONS
WARNING
.