Noritz WHiC56 Service Manual page 32

B
A
Check the resistance between the terminals of
the Gas Proportioning Valve.
Normal
CN101 : Between Red 7 - Blue 6
Check whether the manifold gas pressure can be
adjusted.
Impossible
Check that combustion conditions are normal. (Is the flame small?, Is there lift?, etc.)
Normal Abnormal
Check whether the primary gas pressure
(dynamic pressure) is normal.
Normal
Check whether the burner gas pressure
and fan speed are normal.
Normal
Compare the data indicated on maintenance monitor No.10 and No.20.
Check whether the Burner on indicator is lit by the Dummy Flame*. (at the Flame Rod.)
Shown
Fully close the gas supply valve
With the remote controller turned on (if connected) and open the hot water fixture.
The unit starts sparking, and then connect the Dummy Flame between the flame
rod and earth. Check whether "Burner on indicator" is lit. ("72" should be
indicated after a while.)
Check whether the Burner On Indicator is lit by the Dummy Flame*. (on the Circuit Board.)
In many cases, the error code 11 for ignition failure does not reappear. In some cases the error is caused by fluctuations due to
environmental factors (time, humidity, etc.). If the error does not reappear, also check the items listed below.
Item Check contents
Gas supply
Low primary pressure
The Primary Gas Solenoid Valve (SV0)
The Gas Solenoid Valve-1 (SV1)
Ignition device
Igniter
(faulty spark)
Ignition Plug
Control and Faulty the manifold gas pressure setting
settings
Flame Rod
Gas Proportioning Valve
Other Wiring
When measuring the resistance, disconnect
the connector and check the male side.
50 - 90
* Check the primary pressure (dynamic pressure) at the time of maximum combustion.
Shown
Fully close the gas supply valve.
With the Remote Controller turned on (if connected) and open the hot water fixture. The unit starts sparking, and then connect the Dummy
Flame between CN78 Blue 1 - CN101 Green 3 (earth). Check whether "Burner On Indicator" is lit. ("72" should be indicated after a while.)
Current: DC 1µA or more
BL 6 1 R
R 7 2 BL
W 8 3 G
9 4 W
O 10 5 Y
<CN101>
Fluctuation factors and check procedure
Check whether the gas supply valve is half open.
Check the primary pressure (dynamic pressure) at the time of maximum combustion.
Check whether the error occurs when there is high gas consumption. (The primary gas
pressure (dynamic pressure) may fluctuate during high usage.)
Check whether the cable was caught between the front cover and the casing or not.
Check for faulty insertion of wiring from Igniter to the Ignition Plug.
Check for water on or traces of water on the Ignition Plug.
Check whether the manifold gas pressure can be adjusted and readjust the manifold gas pressure.
Check whether "the grounding wire was caught between the front cover and the casing" or
"the leakage occurred" or not. Check for looseness or faulty connection of grounding screw.
Switch the maximum and minimum burner pressure set button and check that the burner
gas pressure switches smoothly. (Possible cause: Catching of moving coil)
Faulty connection due to looseness of connector pins or incomplete insertion of connectors.
Check whether the cable was caught between the front cover and the casing.
Abnormal
Possible
Check for the burner injector clogging and the gas / model type
setting, then replace the Gas Valve.
Abnormal
Check the gas supply valve, etc.
Adjust the burner gas pressure
Abnormal
and check the gas and model
type setting, etc.
Not shown
Circuit Board
<CN42>
MAIN
W 4 1 BK
CIRCUIT
5 2
<CN101>
6 3
BL 6 1 R BOARD
R 7 2 BL
W 8 3 G
9 4 W
O 10 5 Y
1 BK
2
3 W
4
5 W
6 BL
7
BR
8 GY
9 BK
10 O
11
12 W
<CN10> <CN63>
Check for the wiring (Flame Rod, grounding wire, grounding screw etc.)
- 32 -
Replace the Gas Valve.
Recheck after adjusting
the manifold gas pressure.
Primary gas pressure list
Gas group
Pressure
Maximum
pressure
Minimum
pressure
Check for the Burner injector,
Fan Motor, Burner, clogging.
Not shown
Replace the Circuit Board set.
<CN186>
1 R
2 BK
3 W
4
G
5 BL
6 BL
W 31 32
1 BL
R 29 30
2
V 27 28 BK
<CN78>
O 25 26 G
W 23 24 BK
21 22
19 20 V
BL
17 18 G
O 15 16 O
1 W 13 14 BL
2 11 12
W
3 W 9 10 Y
4 W 7 8 R
1 BL
5 W Y 5 6 Y
2 BL 1 2 3
6 3 4
W R BK
3 BL BK
7 W 1 2 W
<CN38> <CN89> <CN197>
Replace the Flame Rod.
ULPG NG
kPa 3.5 3.0
kPa
2.75 1.13
1 BL
2
<CN78>