YES
FLASHING
1 FLASH - INDOOR FAN DELAY
MODIFIED (HEATING)
2 FLASHES - OPENING OF LIMIT
SWITCH
3 FLASHES - FLAME SENSOR
INDICATES FLAME WITH
CLOSED GAS VALVE
4 FLASHES - LIMIT SWITCH
CYCLED 4 TIMES ON SINGLE
CALL FOR HEAT
5 FLASHES - IGNITION LOCKOUT
(No iginition within 15 minutes)
6 FLASHES - INDUCED DRAFT
MOTOR FAULT
(No signal from the Hall Effect
Sensor for 60 seconds)
7 FLASHES - OPENING OF
ROLLOUT SWITCH
8 FLASHES - HARDWARE OR
SOFTWARE FAULT
9 FLASHES - SOFTWARE
LOCKOUT
30 SECOND OFF DELAY
FOR INDOOR FAN
COMPRESSOR AND
OUTDOOR FAN STOP
IMMEDIATELY
COOLING DEMAND
SATISFIED
1 SECOND ON DELAY
FOR INDOOR FAN
COOLING
COMPRESSOR AND
OUTDOOR FAN MOTOR
START IMMEDIATELY
CALL FOR
ON
LED is
OFF
YES
NO
24 VOLTS
BETWEEN
R & C ON J2?
DEFECTIVE
IGC BOARD
1. BLOWN 5 AMP FUSE
2. DEFECTIVE 24V TRANS.
3. BROKEN WIRE
4. NO POWER TO UNIT
HEATING
COMBUSTION RELAY ON IGC IS ENERGIZED
“W1” FROM BASE CONTROL BOARD ENERGIZES “W”
ON IGC - 1 MINUTE LOCK-ON
COMBUSTION RELAY ENERGIZES INDUCED DRAFT MOTOR (IDM)
THROUGH TERMINAL “CM” ON IGC
IF IDM IS TURNING AT CORRECT SPEED (AT LEAST 2400 RPM), HALL
EFFECT SENSOR SENDS CORRECT SIGNAL TO TERMINAL “J1” ON IGC
IF LIMIT SWITCH AND ROLLOUT
SWITCH ARE CLOSED, IGC SAFETY
LOGIC WILL INITIATE IGNITION
SEQUENCE
IGC SAFETY LOGIC OPENS GAS
VALVE FOR 5 SECONDS
IGC HIGH VOLTAGE
TRANSFORMER CREATES A
10,000 VOLT SPARK FOR 5
SECONDS
IGC SAFETY LOGIC WILL SHUT
OFF GAS VALVE AND SPARK
20 SECOND PURGE OF HEAT
EXCHANGER
IS THIS THE
33RD RETRY? (0R 15
MINUTES)
IGNITION LOCKOUT
(5 FLASHES OF LED)
NO
NO
YES
YES
NO
YES
SUBTRACT 5 SECONDS (OR
ANOTHER 5 SECONDS) FROM
INDOOR FAN ON TIME DELAY
DOES IGC DETECT
.2 MICROAMPS FOR 2
SECONDS
AFTER 45 SECONDS (OR LESS IF THE TIMING
HAS BEEN REDUCED DUE TO LIMIT SWITCH
TRIPS) IGC WILL ENERGIZE BLOWER RELAY
DID LIMIT
SWITCH OPEN BEFORE THE 45
SECONDS (OR THE MODIFIED
TIME) HAS TIMED OUT?
NORMAL HEATING OPERATION
HEATING DEMAND SATISFIED
IDM STOPS, SAFETY LOGIC SHUTS OFF GAS VALVE
45 SECOND BLOWER SHUTOFF DELAY
(DELAY EXTENDED BY 5 SECONDS FOR EACH LIMIT SWITCH TRIP -
MAXIMUM DELAY: 3 MINUTES)
Fig. 21 — IGC Service Analysis Logic
LEGEND
NOTE: Thermostat Fan Switch in the
“AUTO” position.
IDM — Induced-Draft Motor
IGC — Integrated Gas Unit Controller
A48-5656TF
To Next Page
Loading...
