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ecoTEC plus 937 installation and maintenance manual
8 Troubleshooting
8.1
Logical fault finding procedure
Carry out the following checks before the actual
troubleshooting:
• Carry out the tests to check electrical safety (see
Section "Preparatory Checks on the Electrical
System").
• Check that the external power supply for the combi
boiler is switched on and that there is a supply voltage
of 230 V AC between the connections "L" and "N".
• Check that the gas supply to the combi boiler is
switched on.
• Check that the combi boiler has been properly purged
and that there is a supply pressure of 20 mbar the
inlet to the boiler. (See Section "Gas Supply".)
• Check that the heating system is filled with water and
that there is a pressure of between 1.0 and 1.5 mbar.
Otherwise top up the system and bleed. (See Section
"Filling the Heating System".)
• Check that the isolation valves in the flow and return
lines of the combi boiler are open.
• Check that the mains switch is set to "ON".
• Set the temperature of the central heating to
"Maximum".
• Set the temperature of the hot water preparation to
"Maximum".
• Check that all external controllers are switched on and
are demanding heat (if no external controllers are
fitted, the connections 3 and 4 on the combi boiler
terminal must be connected together).
• Check that the burner anti-cycling time mode on the
combi boiler is not active.
8.1.1 Status
codes
The status codes which you can see in the display
provide information concerning the current operating
status of the unit.
Proceed as follows to display the status codes:
Fig. 8.1 Display of status codes
• Press the "
i
" button.
The display shows the status code e.g.
S.04
for the
"Burner mode - heating".
The status code display can be de-activated as follows:
• Press the "
i
" button.
or
• Do not press any button for about 4 minutes.
The current heating flow temperature appears in the
display again.
Display
Meaning
Heating mode:
S.0
No heat demand
S.1
Fan running
S.2
Pump running
S.3
Ignition
S.4
Burner ignited
S.5
Fan and pump running
S.6
Fan over run
S.7
Pump overrun time
S.8
Anti-cycling mode
Table 8.1 Status codes (continuation see next page)
Troubleshooting 8
