STANDBY MODE
When the boiler is switched on, it starts up in Stand-by mode, as shown
in the figure above.
This is the standard mode of the MCBA. The MCBA automatically returns
to this mode after 20 minutes if no key is pressed on the display. When
one or more parameters were stored, the new parameters will become
active.
The first digit indicates the boiler’s current status, depending on the
situation of the boiler and the burner. The last two digits indicate the
boiler temperature.
Status
Boiler function
Standby, no heat demand
Fan pre-purge/post-purge
Ignition
Operation of the burner for heating
Operation of the burner for domestic hot water
Waiting for signal from the air pressure switch or to
obtain number of start revolutions.
The burner is off because the set value has been
reached. There is still a demand for heat.
Circulator time delay after the heating demand.
Circulator time delay after the hot water demand.
Blocked burner:
Please refer to paragraph "
MCBA blockage and
error codes
" on pages
28
and
29
If the burner is blocked for one of the above reasons, the screen display
alternates between "9" and the temperature (last two digits) and “b”
with the error code.
Once the cause of the blocking has been resolved, the burner
starts up automatically after a maximum of 150 seconds.
Status
Boiler function
Internal adjustment — Three-way valve
Burner on for holding boiler warm
Test function: max RPM in CH mode
Test function: min RPM in CH mode
Test function: burner on with fixed fan speed
MCBA PARAMETERS FOR THE SPECIALIST
PARAMETER MODE
SETTING THE MCBA PARAMETERS
To access Parameter mode when the system is in Standby mode, press
the “MODE” key once.
To scroll through the list of parameters press “STEP”. To modify the
value of the parameter, use the “+” or "–" keys.
Next, press “STORE” to save the modified value. The screen will flash
once to confirm the data has been saved.
To activate the modified parameters, press “MODE” again (this will
switch you to Info mode). However, if you do not press any key, the
system returns to Standby mode after 20 minutes and activates the
changes.
Factory setting
Display
Description of the
parameters
HM 25 TC
HM 35 TC
HM 70 TC
HM 85 TC
STEP
Setting the hot water
temperature
STEP
Hot water (
DHW
)
production
00
= Off
01
= On
STEP
Switching heating On/Off
00
= Off
01
= On
STEP
Maximum temperature
in central heating (
CH
)
mode
Display
MODE
EN • 22
664Y5300 • A
E
N
FR
R
U
P
L
DE
IT
ES
N
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