S-314 Checking Flame Sensor - Goodman GMEC96 Service Instructions Manual

SERVICING
C A U TIO N - 1 20 V
S T 1
K 1 1
K 2 K 1
K 3
R 92
Q 3
Q 2
W 39
W 35
Q 72
W 3
Q 6
R 20 1
R 20 2
R 20 0
E 35
R 586
F LA M E
R 50
R 588
C U R R E N T
W 1 5
R 39 E 36
W 1 6
R 40
W 33
W 1
W 1 9
R 49
W 1 0
C 1 4
R 20 4
G L1
R 35
W 46
M 2
W 7
R 566
Q 9
R 578
S 1
E 1 2
R 568
1
2 U 3
R 580
3
R 557
4
O N
O F F
R 76
W 40
R 1 1 8
R 570
S 2
1 R 82
R 581
2 W 52
R 562
3
R 38
O F F O N
R 563
R 71
R 584
R 1 1 5
Q 1 3
W 49
D S 1
W 2
Q 1 1
R 29
R 564
R 3
R 573
R 4
R 553
S W 3
R 1 5
R 1 0
Y l0 Y W 2 R
W 1
R
W 20
W 37
R 27
S T 3
R 1 30
R 1 1
R 1 3
PCBBF133 Control Board
4. After the ignitor warmup time, begin checking for 24
volts to the gas valve. Voltage will be present for four
seconds only if proof of flame has been established.
5. If proof of flame was established voltage will be provided
to the air circulation blower following the heat on delay
period.

S-314 CHECKING FLAME SENSOR

A flame sensing device is used in conjunction with the igni-
tion control module to prove combustion. If proof of flame is
not present the control will de-energize the gas valve and
"retry" for ignition or lockout.
66
N E U TR A LS
S T 5
S T 2
W 1 8
K 1 0
Q 71
K 6
Q 7
R 60
Q 5
W 34
W 1 1
R 58
Q 70
C 60
C 1 5 W 44
W 31
R 73
W 53
R 78
R 74
Q 60
R 79
W 1 2
W 1 3
R 81 W 30
R 61
K 5
R 85
R 77
W 29
Q 1 0
K 9
Q 4
Q 1 4
R 780
S T 6
R 59
W 32
R 70
R 53
R 524
R 63
R 41
R 75
R 87
R 31
R 9
R V3
G C TW IN
R 1 1 9
R V4
W 51
R 91
C 1 3
E 39
C R 1 3
W 24
W 36
W 1 4
R 1 8
R 65
W 22 R 21
R 1 7
S T 4
R 1 2
F 1
R 33
R 1 6
R 2
R 54
R 44
E 26
W 4
HIGH VOLTAGE
D ALL
ISCONNECT
INSTALLING THIS UNIT.
F
BE PRESENT. AILURE TO DO SO MAY CAUSE PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
Flame current can be measured in two ways:
1. Putting a D.C. microamp meter in series with the
flame rod
E 40
K 4
2. Putting a D.C. volt meter across the two solder pads
in the flame current section of the control board.
1 D.C. volt = 1 microamp.
C 1 1
Flame Current
Solder Pads
E 22
E 27
L
INE VOLTAGE NOW PRESENT
3. As soon as flame is established a micro-amp reading
should be evident once proof of flame (micro-amp read-
ing) is established, the hot surface ignitor will be de-
energized.
4. The Integrated Ignition controls will have 1 to 4 micro-
amps. If the micro-amp reading is less than the mini-
mum specified, check for high resistance wiring con-
nections, sensor to burner gap, dirty flame sensor, or
poor grounding.
5. If absolutely no reading, check for continuity on all com-
ponents and if good - replace ignition control module.
NOTE: Contaminated fuel or combustion air can create a
nearly invisible coating on the flame sensor. This coating
works as an insulator causing a loss in the flame sense
signal. If this situation occurs the flame sensor must be
cleaned with steel wool.
WARNING
POWER BEFORE SERVICING OR
M
ULTIPLE POWER SOURCES MAY
WARNING