Heat Controller, Inc.
MGD-B SERIES GAS FURNACE
Owner’s Manual
PRE-TROUB
LESHOOTING CHECK LI
ST
YOU MUST HAVE THE FOLLOWI
NG TOOLS TO PREFORM THE
TROUBLESHOOTING
DESCRIBED
B
ELOW
:
1 - VOLT, AMP, OHM METER
VOLTAGE RANGE 0 - 300 VOLTS
VI
SE
GRI
P PLI
ERS
CURRENT RANGE 0.0 AMPS TO 1 MI
CROAMPS (
0.000001
AMPS)
. IF Y
OU CURRENT METER DOES NOT
HAVE A MI
CROAMP
(µa) READING;
mA.
YOU CAN USE THE MI
LLI
AMP
(mA)
PROVIDING
THE SCALE READS
0.000
G18D SERIES CONTROL
BOARD
TROUBLE SHOOTING GUIDE
8
G
1
8
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e
ri
e
s
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s
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or
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ro
du
ct
s
In
c.
/
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or
t W
or
th
, T
X
7
61
06
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SH
1
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N
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CT
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SE
N
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N
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SE
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RO
A
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M
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IF
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M
E
SE
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CU
RR
EN
T
RE
AD
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G
IS
BE
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EN
1
.0
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IC
RO
A
M
P
(0
.0
00
00
1
A
M
P)
A
N
D
3
.7
M
IC
RO
A
M
PS
(0
.0
00
00
37
AM
PS)
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N
T
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YE
LLO
W
WI
RE
. T
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A
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LY
3
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RO
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M
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SE
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ICK
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ECT
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N
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7
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ICR
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A
M
PS
(0
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37
A
M
PS
) G
O
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3
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IC
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M
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(0
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M
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(0
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M
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N
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3
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IC
RO
AM
PS
(0
.0
00
00
1
- 0
.0
00
00
37
A
M
PS)
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TH
T
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RR
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N
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TR
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BO
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; T
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N
PLU
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TH
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9
PI
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T
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P
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(O
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(
Ω
) T
EST
)
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(
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WS
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∞
SY
M
BO
L
(SH
O
WS
A
O
PE
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RE
);
TH
EN
R
EP
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CE
T
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GO
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3
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3
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M
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BU
RN
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M
P
(0
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IC
RO
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M
PS
(0
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37
A
M
PS)
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EN
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BU
RN
ER
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A
T
TH
E
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M
E
SE
N
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R.
IF
TH
E
BU
RN
ER
FLA
M
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RR
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A
D
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IS
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BE
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EN
1
.0
-
3.
7
M
IC
RO
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PS
(0
.0
00
00
1
- 0
.0
00
00
37
A
M
PS
) A
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T
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BU
RN
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LLY
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EN
D
SE
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P
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L
TH
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N
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R
IS
IN
T
H
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BU
RN
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R
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N
TI
L
FLA
M
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M
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RO
A
M
PS
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RE
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ET
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EN
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3.
7
M
IC
RO
AM
PS
(0
.0
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1
-
0.
00
00
03
7
A
M
PS)
.
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SE
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IS
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RI
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PL
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RS
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RO
D
W
HE
N
BE
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N
G
FL
A
M
E
SE
N
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R
SO
T
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M
IC
DO
ES
N
O
T
BR
EA
K
O
R
CR
A
CK
.
IF
N
O
M
IC
RO
A
M
P
RE
A
D
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G
IS
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EV
EN
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FT
ER
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EN
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IN
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TH
E
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P
TO
A
9
0
D
EG
RE
E
A
N
GLE
IN
FR
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N
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F
TH
E
BU
RN
ER
T
H
EN
R
EP
LA
CE
T
H
E
SE
N
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R.
IF
A
R
EA
D
IN
G
A
BO
VE
1
.0
M
IC
RO
AM
PS
IS
PR
ESE
N
T
BU
T
BU
RN
ER
WO
N
'T
ST
A
Y
LI
T
GO
T
O
ST
EP
4
.
4
TH
ER
E
IS
A
B
RO
KE
N
WI
RE
T
O
T
H
E
GAS
VAL
VE
O
R
O
N
E
O
F
TH
E
GAS
VA
LV
E
WI
RE
S
H
A
S
A
BAD
CO
N
N
EC
TI
O
N
.
U
SE
O
H
M
(
Ω
)
M
ET
ER
T
O
D
ET
ER
M
IN
E
WH
IC
H
WI
RE
T
O
T
H
E
GAS
VA
LV
E
IS
D
EFE
CT
IV
E AN
D REPLACE THE WIRES.
RE
M
O
VE
T
H
E
9
PI
N
P
LU
G
FR
O
M
T
H
E
CO
N
TR
O
L
BO
A
RD
A
N
D
T
H
E
WI
RE
S
FR
O
M
T
H
E
GAS
VALV
E.
U
SE
A
O
H
M
(
Ω
) M
ET
ER
T
O
D
O
A
R
ESI
ST
A
N
CE
T
EST
O
N
B
O
TH
O
F
TH
E
BR
O
WN
WI
RE
S
FR
O
M
T
H
E
PI
N
O
N
T
H
E
9
PI
N
P
LU
G
TO
T
H
E
GAS
VA
LV
E.
WH
EN
P
RE
FO
RM
IN
G
TH
IS
TE
ST
M
O
VE
T
H
E
WI
RE
H
A
RN
ESS
TO
C
H
EC
K
FO
R
A
B
AD
C
O
N
N
EC
TI
O
N
. I
F
A
C
O
N
N
EC
TI
O
N
IS
BA
D
T
H
E
M
ET
ER
R
EA
D
IN
G
WI
LL
CH
A
N
GE
FR
O
M
Z
ER
O
O
H
M
S
TO
SH
O
WI
N
G
O
PE
N
O
R
TH
E
IN
FI
N
IT
Y
(
∞
) SY
M
BO
L.
IF
A
WI
RE
IS
FO
U
N
D
T
O
B
E
D
EFE
CT
IV
E
O
R
H
A
S
A
B
AD
CO
N
N
EC
TI
O
N
; T
H
EN
R
EP
LA
CE
T
H
E
WI
RE
O
R
WI
RE
H
A
RN
ESS
. I
F
TH
E
BO
TH
W
IR
ES
A
RE
SH
O
WI
N
G
CLO
SE
T
O
Z
ER
O
O
H
M
S
(
Ω
) T
H
EN
GO
TO
ST
EP
5
.
5
CO
N
TR
O
L
BO
AR
D
IS
D
EFE
CT
IV
E
U
SE
A
M
IC
RO
AM
P
M
ET
ER
T
O
M
EA
SU
RE
T
H
E
FLA
M
E
SE
N
SO
R
CU
RR
EN
T
RE
AD
IN
G.
T
H
E
RE
AD
IN
G
M
U
ST
B
E
BE
TWE
EN
1
.0
M
IC
RO
A
M
P
(0
.0
00
00
1
AM
P)
A
N
D
3
.7
M
IC
RO
AM
PS
(0
.0
00
00
37
A
M
PS)
WI
TH
T
H
E
BU
RN
ER
FLA
M
E
PR
ESE
N
T
A
T
TH
E
SE
N
SO
R.
IF
TH
E
BU
RN
ER
FLA
M
E
SE
N
SO
R
CU
RR
EN
T
RE
A
D
IN
G
IS
BE
TWE
EN
1
.0
-
3.
7
M
IC
RO
A
M
PS
(0
.0
00
00
1
- 0
.0
00
00
37
A
M
PS)
A
N
D
T
H
E
BU
RN
ER
W
ILL
N
O
T
ST
A
Y
LI
T
TH
EN
R
EP
LA
CE
T
H
E
CO
N
TR
O
L
BO
A
RD
O
N
LY
IF
TH
E
CH
EC
KS
IN
ST
EP
S
1,
2,
3,
A
N
D
4
H
A
VE
B
EE
N
P
RE
FO
RM
ED
.
MGD-B SERIES CONTROL
BOARD
6
