User and technical staff manual
35
14.2 Other failures
Failures that do not have an error code shown on the boiler’s display, are shown in Table 5:
Table 5
Failure
Reason of failure
Troubleshooting
Boiler doesn’t switch on
Lack of electricity
Address to the electricity service
Fuse is burnt
Replace the fuse on the board
Heat carrier or water entry on the
electronic board
Dry the board by means of warm air or leave
it for 2 days in a dry place for full ware
evaporation
Electronic board failure
(RESET doesn’t help)
De-energize and re-start boiler
Replace the electronic board
Claps in the burner
Minimal gas pressure and ignition
power are wrong adjusted
Adjust minimal gas pressure (see p. 11.4,
page 26) and ignition power “P0” (see p.
13.3.1, page 30)
Insufficient air supply
Clean the tube or air inlet duct
Electrode spark of ignition plug slips
on the edge of burner section or the
shell of combustion chamber
Bend the ignition plug or shell of
combustion chamber allowing a spark to slip
on the aperture area of the nozzles of burner
section
Burner block is contaminated
Clean the burner block (see p. 16.1.1, page
37)
Smell of gas
Gas leakage
Check the whole gas circuit for air-
tightness (see p.8.2, page 14), remove gas
leakage
Little hot water output
or its absence
Insufficient inlet DHW water
pressure
Address to the Housing and Public utilities
service
Water filter is contaminated
Clean the filer on the DHW line
Secondary heat exchanger is
contaminated
Clean the heat exchanger (see p. 16.1.3,
page 38)
Set water temperature
is not maintained (too
high)
High incoming water temperature
Increase water flow through the DHW or
dilute hot water with cold water not
permitting reduction of water flow through
the DHW circuit
Little water flow through DHW
circuit
Increase water flow through DHW
The boiler is nor
operating in the
heating mode (Bur is
operating in the DHW
mode)
No plug wire in the room thermostat
Install the plug wire into the room
thermostat
Room thermostat’s plug wire
connecting contacts 28 and 29 is out
of order (see Annex III, page 66)
Replace the room thermostat’s plug wire
Failure of room thermostat (if it is
installed)
Replace a room thermostat
Inlet water temperature
in the heating system is
lower than the set one
Failure of CH temperature sensor
Replace the temperature sensor
Boiler is in stand-by
mode, a symbol«- -» is
displayed but boiler
doesn’t react to the
pressed control buttons
Power voltage is over 190 ÷ 250 V
Restore power voltage in range 190 ÷ 250
V. Within 30 seconds the boiler will be
launched automatically in the previous
mode that boiler was in before the power
voltage went out of the range 190 ÷ 250 V