Noritz NR501-OD Service Manual page 38

A B
Check the voltage to the Primary Gas Solenoid Valve (SV0)
and the Gas Solenoid Va lve-1 (SV1).
Normal
1 SV0 CN10
DC1 - 16V
2 SV1 CN10
DC1 - 16V
Check the resistance to the Primary Gas Solenoid Valve (SV0)
and the Gas Solenoid Valve-1 (SV1).
Normal
1 SV0 CN10
20 - 35
2 SV1 CN10
35 - 65
Check the voltage between the terminals of the Gas
Normal
DC 0.3 - 15 V
Check the voltage between the Gas Propor tio
(on the Circuit Board).
Normal
CN10 : Between Red 4 - Blue 3
Check the resistance between the terminals of
the Gas Proportion n i
Normal
CN10 : Between Red 4 - Blue 3
50 - 80
Check whether the manifold gas pressure can be
adjusted.
Impossible
A
: Between White 10 - Blue 11
: Between Black 8 - Blue 11
Circuit Board
1
14
2
13
12 BL
3 BL 11 W
10 R
9 Y
4 R
8
7
6 BK
5 W
5 BK
4 W
6 O 3 W
2 BK
1 W
7 GY
<CN63>
8 BK <CN135>
9
<CN78>
10 W
2 1
1
11 BL BL 2
3 BL
4 R
12
5 W
6 O
7 GY
13 W
8 BK <CN10>
9
14 10 W
11 BL
12
15 BL
6 BK 13 W
14
5 R
15 BL
4
3
2 W
<CN10>
1 W
<CN42>
: Between White 10 - Blue 11
When measuring the resistance, disconnect the connector
and check from the disconnected connector side.
: Between Black 8 - Blue 11
Abnormal
DC 0.3 - 15V
Circuit Board
1
14
2
13
12 BL
3
BL 11 W
10 R
4 R 9 Y
8
7
5 W
6 BK
5 BK
6 O
4 W
3 W
7 GY
2 BK
1 W
8 BK
<CN63>
9 <CN135>
10 W
11 BL
<CN78>
12 2
1
1 BL 2
13 W 3 BL
4 R
14 5 W
6
O
7
15 GY
BL
8 BK <CN10>
9
10 W
<CN10> 11 BL
12
6 BK 13 W
5 R 14
15 BL
4
3
2 W
1 W
<CN42>
g V a v l . e
When measuring the resistance, disconnect
the connector and check the male side.
38
Abnormal
12 W
11 Y
10 O
9 R
8
7
Main
6 BK
5 V
Circuit
4 G
3 O
Board
2 Y
1 W
<CN59>
1
2
1 2 3
3 4 3 2 1
4 BL
4 R
3 BL BR Y BL R
5 O
2 BL
6 <CN27>
Y
1 R
7
W
<CN142>
Po wer
<CN104>
Circuit
3 R
Board
2 BL
1 G
<CN101>
<CN89B>
3
2
1
<CN75>
3 2 1
BL/W R/ R G
<CN102>
<CN89A>
Abnormal
Check for improper connection of wiring.
then replace the Gas Valve or Manifold Plate .
P o r p o t r o i n n i g V l a e v o ( n t h e o c
i n g n V l a e v Abnormal
12 W
11 Y
10 O
9 R
8
7
Main
6 BK
5 V
Circuit
4 G
3 O
Board
2 Y
1 W
<CN59>
1
2
1 2 3
3 4 3 2 1
4 BL
4 R
3 BL BR Y BL R
5 O
2 BL
6 Y <CN27>
1 R
7 W
<CN142>
Po wer
<CN104>
Circuit
3 R
Board
2 BL
1 G
<CN101>
<CN89B>
3
2
1
<CN75>
3 2 1
BL/W R/ R G
<CN89A> <CN102>
Check for improper connection of wiring .
Abnormal
Po ssible
Check for the burner injector clogging and the gas / model type
setting, then replace the Gas Valve.
Replace the Circuit Board set.
* It is not necessary to replace the
Display Window Circuit Board.
Display Window
Fuse
Circuit Board
Data
Displ ay
W 3 1 W
BK 4 2 BK
<CN92>
Dip Switch
1 2 3 4
R BL BL BL
<CN142>
n n c e o t . ) r
Replace the Circuit Board set.
* It is not necessary to replace the
Display Window Circuit Board.
Display Window
Fuse
Circuit Board
Data
Displ ay
W 3 1 W
BK 4 2 BK
<CN92>
Dip Switch
1 2 3 4
R BL BL BL
<CN142>
Replace the Gas Valve.
Recheck after adjusting
the manifold gas pressure.