Rinnai COMBI i060C, Installation And Operation Manual, Page: 103 / 136

Rinnai I-Series Condensing Boiler Combi Manual 103
PC Board

PC Board circuit error.

Replace PC Board.
Solenoid Valve Circuit

Ensure Dip switch 5 on the PC Board is in
the OFF position (default).

Ensure the gas control wire is not loose or
damaged.

Replace the PC Board.
Flame Rod

Check the flame rod and wire for damage.

Ensure the flame rod and wire are not wet.

If there is no issue with the flame rod or
wiring, replace the PC Board.
Freeze Issue

The boiler checks the heat exchanger
temperature at the time of operation.

If the temperature is too low, an error will
occur.

Check if there is freezing in the boiler or
CH system.
PC Board Mismatch

This code occurs when the PC Board and
the internal logic do not match.

Check if the software versions of the board
and operation board do not match.
Scale Buildup in Heat Exchanger

Flush the DHW plate heat exchanger.

The LC code will reset automatically when
scaling is removed. If the LC code remains,
check the DHW thermistor, flow sensor or
boiler pump.
Maintenance Indicator

This code is a placeholder in diagnostic
code history indicating a service provider
performed maintenance or service.

Enter this code after performing service by
pressing and holding the Up button, then
press and hold the Down button, and then
press the DHW button simultaneously.
will appear on the display.
No
Code
Nothing happens when DHW water flow is
activated

Verify the minimum flow rate required
to fire the boiler is seen.

Measure the resistance of the flow
control sensor.*

Clean the inlet water supply filter.

On new installations, ensure the hot and
cold water lines are not reversed.

Confirm the inlet water temperature is
not too high.

Ensure the integrated boiler pump
operates properly.

Ensure the DHW operation switch is on.
No
Code
Decreasing or fluctuating DHW water flow
volume

Ensure the gas pressure is proper.

Ensure the water pressure is proper.

Ensure the inlet water filter for DHW is
clean.

Ensure there is not lime scale buildup
present.

Ensure the vent and vent settings are
properly set up.

If a DHW recirculation system is used,
the DHW flow volume may vary slightly.

Ensure all air has been purged from the
system.

Ensure the pump is set to speed 3.

During simultaneous CH and DHW
operation mode, it is possible to see
decreased DHW flow.
No
Code
Fluctuating DHW outgoing temperature

Ensure the gas pressure is proper.

Ensure the water pressure is proper.

Ensure the DHW thermistor, flow servo,
and bypass servo are in good condition.

Ensure the inlet filter for DHW is clean.

If a DHW recirculation system is used,
the DHW temperature may vary slightly.

Ensure all air is removed from the
system.
No
Code
Boiler does not start heating with a heating
demand present

Supply temperature or return
temperature inside the boiler may be
too hot.

Ensure the pump operates properly.

If there is a demand immediately after
using DHW, wait at least three minutes
for operation.
* See “Electrical Diagnostics” on Technical Data
Sheet located on inside front cover of boiler.
Up and Down
Press the DHW
button