Service manual
VI - TROUBLESHOOTING (cont.)
QUICK REFERENCE DIAGNOSTIC POINTS
IMPORTANT SAFETY NOTES:
There are a number of (live) tests that are required when fault finding this product. Extreme care
should be used at all times to avoid contact with energized components inside the water heater.
Only trained and qualified service agencies should attempt to repair this product.
R
emember, before checking for resistance readings, you should disconnect the power source
(unplug it) to the unit and isolate the item to be checked from the circuit.
(TR) Transformer:
Wire color Voltage Resistance Connector # Pin #'s
Black
~
White 100
~
120 VAC 51
~
63 ohms F9 1
~
2
Blue
~
Brown 110
~
120 VAC 51
~
63 ohms F7 1
~
3
(SV0, SV1, SV2, SV3 and POV) Gas valve and Modulating solenoids: (Set meter above 2K)
(SV0) Pink
~
Black 80
~
100 VDC 1,8K
~
2K ohms E1 1
~
2
(SV1) Black
~
Yellow 80
~
100 VDC 1,8K
~
2K ohms E2 2
~
3
(SV2) Black
~
Blue 80
~
100 VDC 1,8K
~
2K ohms E3 2
~
4
(SV3) Black
~
Brown 80
~
100 VDC 1,8K
~
2K ohms E4 2
~
5
(POV) Pink
~
Pink 2
~
15 VDC 67
~
81 ohms C2 3
~
4
(M) Water Flow Control Device Servo or Geared Motor:
Red
~
Blue 11
~
13 VDC 22
~
26 ohms B2 9
~
10
Grey
~
Brown 4
~
6 VDC N/A B2 5
~
7
Grey
~
Yellow N/A N/A B2 5
~
8
Grey
~
Orange 11
~
14 VDC N/A B2 5
~
6
NOTE: The grey wire listed above turns to black at B connector on the PCB, the orange wire turns to red.
(QS) Water Flow Sensor:
Black
~
Red 11
~
13 VDC 5.5K
~
6.2K B4 5
~
6
Yellow
~
Black 4
~
7 VDC 1 meg
~
1.4 meg B4 1
~
5
By-pass Flow Control:
Brown
~
White2
~
6 VDC Unit in operating G4
~
G5 4
~
5
Orange
~
White mode G2
~
G5 2
~
5
Yellow
~
White 15
~
35K G1
~
G5 1
~
5
Red
~
White/Ground 3
~
5
(IG) Ignition System:
Grey
~
Grey 90
~
100 VAC N/A F8 2
~
3
(FM) Combustion Fan Motor:
Red
~
Black 6
~
45 VDC N/A A1 1
~
2
White
~
Black 6
~
45 VDC 9.2K
~
9.4K A1 2
~
4
Yellow
~
Black 11
~
13 VDC 3.5K
~
3.9K A1 2
~
3
Set your meter to the Hertz scale. Reading across the red and yellow wires at terminals 2 and 3 you
should read between 60 and 350 Hertz.
25