Installation / Operation Instruction Manual
64
Problem solving
RTG-K-199/160N/X1 – 6 720 817 984 (2022/06)
9Problem solving
9.1 Error code diagnostics
To remove error code from the display, press and hold on/off
button for 3 seconds.
Fitting, maintenance and repair must only be carried out by
qualified contractors. The following table describes the
solutions for possible problems (solutions followed by footnote
must only be carried out by qualified contractors).
Display Description Solution
A0 Water temperature sensor [17] [19] [20]
disconnected or damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A1 Air temperature inside the cabinet [18] is above
158 °F (70 °C). Appliance regulates power to protect
against overheat.
▶ External air temperature is above 140 °F (60 °C).
▶ Check for flue leakages inside the appliance
1)
A2 External water temperature sensor/aquastat [21]
disconnected, damaged or not properly installed.
▶ Check temperature sensor and associated
connections.
1)
2)
▶ Check sensor position in the tank well.
▶ Verify if correct recirculation settings are
selected (section 6.5.4).
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A3 Flue gases temperature sensor [15] disconnected or
damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A4 Air temperature sensor [18] disconnected or
damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A5 Condensing unit flue temperature sensor [16]
disconnected or damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A6 Inlet cold water temperature sensor [20]
disconnected or damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A7 Heat exchanger hot water temperature sensor [16]
disconnected or damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A8 Outlet hot water temperature sensor [17]
disconnected or damaged.
▶ Check sensor wire connections.
1)
2)
▶ Replace the sensor and/or wire connections, if
the problem persists.
1)
A9
3)
Incorrect output power (too low). ▶ Check gas inlet pressure ( section 4.16).
1)
▶ Check water temperature sensors [17][19][20]
and water flow sensor [14] wire connections.
▶ Check connections or replace sensor(
section 11), replace any if it is not according to
specification.
1)2)