Immergas HERCULES Condensing 26 2 E Manual page 50

Technical Documentation
Low temperature zones 2
and 3 safety thermostat
block
Flue safety thermostat
block
Insufficient circulation
Boiler pump post
circulation
Sealed chamber post-ven-
tilation
Sealed chamber post-
ventilation following
overheating safety block
intervention
Flow NTC breakage
(B1)
Low temperature zones 2
and 3 flow NTC breakage
Return probe resistance
breakage
(R9)
Breakage of the NTC DHW
probe (B2)
Flow over-heating ventila-
tion
STHCkW ed 0409
If the contact of the water overheating thermostat is opened (temperature of the primary
circuit exceeding 55 °C), functioning of the respective CH zone is blocked.
To re-start the appliance, press the "Reset" button "C" and then make a central heating
or domestic hot water request.
If the contact of the flue overheating thermostat is opened (temperature of the external part
of the condensation module exceeding 110 °C) owing to the combustion impurities deposited
on the heat exchanger (soot, oxidations, etc...), boiler functioning is blocked.
To re-start the appliance, press the "Reset" button "C" and then make a central heating
or domestic hot water request.
To prevent overheating of the water-gas heat exchanger if the pump is blocked or due to
little circulation in the primary circuit, when the CH NTC flow probe (B1) detects an
increase in the temperature exceeding 5 °C per second (for more than 2 consecutive seconds),
the burner is switched off.
Re-start takes place when the flow temperature falls below 43°C.
To prevent overheating of the water-gas heat exchanger, at the end of CH (room thermostat
opening), anti-freeze or "chimney sweep" request, the boiler pump (M1) is kept working
for a period of 10 seconds.
At the end of every DHW request, the boiler pump (M1) is left running for 60 secon-
ds.
The combustion chamber is washed after switch-off of the burner at the end of any request
and the fan works for 35 seconds.
After burner switch-off following an overheating block (water or flue gas), the fan is made
to work for 510 seconds (8.5 min) at a speed of about 1/3 of the maximum set.
The breakage of the central heating flow probe (B1) is signalled by the relative anomaly
and prevents functioning both in the central heating and domestic hot water modes.
The breakage of the flow probe is signalled by the relative anomaly and prevents the func-
tioning of the respective low temperature central heating zone.
The breakage of the return probe resistance (R9) is signalled by the return probe anom-
aly.
The breakage of the DHW outlet probe (B2) is signalled by the relative anomaly and
prevents functioning in DHW mode, but functioning in CH mode is allowed.
T prevent overheating of the water-gas heat exchanger, if the boiler temperature detected
by the NTC flow probe (B1) exceeds 105 °C, the fan is made to work until the tempera-
ture drops below 100 °C.
48
Technical Documentation
HERCULES Condensing Export