Rinnai REU-V1620WG Service Manual page 34

10. Overheat Switch Circuit
Measure resistance between Overheat Switch terminals. (B
Ω
Normal: < 1
If normal, replace PCB.
Faulty: Replace Overheat Switch.
Note: If Thermal fuse or Overheat Switch were faulty.
a.) Check heater for damage
b.) Confirm gas type and combustion dipswitch settings
c.) Confirm test point pressure.
11. Water Flow Sensor
a.)
Measure voltage between Red - Black of relay connector (B
Normal: DC 11~13V
If normal, proceed to
Faulty: Replace PCB.
b.)
Measure voltage between Yellow - Black of relay connector (B
Normal: DC 4~7V
If normal, proceed to 2.
Faulty: Replace water flow sensor.
Note: For controller readout of water flow whilst operational refer maintenance monitor. (Chapter
17) No. 1.
12. Water Flow Servo Circuit
a.) Disconnect relay connector (G1), and measure voltage between Red (+) and Black (-) on
PCB unit side.
Normal: DC11-13V
If normal: proceed to c.).
Faulty: Replace PCB unit.
b.) Measure voltage between Black and Yellow with relay connector (G
flowing, water flow servo fully open).
Normal: DC4~6V
Faulty: Replace Water Flow Servo with Water Flow Servo.
c.)
Measure voltage between Black and Brown with relay connector (G
flowing, water flow servo fully open).
Normal: DC4~6V
Faulty: Replace Water Flow Servo and Water Flow Sensor.
Infinity REU-V1616W / REU-V1620W / REU-V2018W / REU-V2020W- 29-
b
.
).
4
).
2
).
2
) connected (with no water
1
) connected (with no water
1
Issue 2 - 21/03/06 ©Rinnai