Rinnai INFINITY REU-3203W Service Manual page 35

6. Thermal Fuse Circuit .
7. Overheat Switch Circuit.
8. Water Flow Sensor
Infinity REU-3203W
Check the Thermal Fuse.
Disconnect relay connector (F
resistance between Red and Red.
Ω
Normal: < 1
If normal, replace PCB.
Faulty: Replace Thermal Fuse if after
confirming there is no damage to the
appliance.
Measure resistance between Overheat Switch
terminals (F ).
2
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.
a.)
Measure voltage between Red - Black of
relay connector (E
Normal: DC 11~13V
If normal, proceed to
Faulty: Replace PCB.
b.)
Measure voltage between Yellow - Black
of relay connector (E
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.
- 30 -
) and measure
1
).
3
b .
).
3
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