54
9 Parts replacement
Instructions for installation and servicing ecoMAX
54
9.7 Replacement of the electronic control board
Danger:
Ensure you observe the safety precautions
when replacing this component.
• Turn off boiler.
• Remove front casing.
• Lower control box.
• Unclip the back cover from the electronics box and
open the cover.
• Unclip the front cover from the electronics box and
remove the cover.
• Disconnect all wires from the circuit board.
• Unclip the circuit board and remove.
• Remove the display unit and (if fitted) the built–in
timer from the electronics box.
• Clip the new circuit board into position in the electro-
nics box, reconnect all plug–in wires and refit back
cover of the switch box by clipping the cover back into
position.
• Raise the electronics box and reinstall the display unit
and (if fitted) the built–in timer. The display unit and
built–in timer are connected using the contact pins on
the circuit board.
• Recommission boiler as previously detailed.
The new circuit board must be adapted to the heating unit
and its system. To do so, carry out the adjustments to the
display system of the heating unit as shown in Tab. 9.1.
Note:
The values in Tab. 9.1 that appear in bold script
MUST be adjusted. All other values can be
adjusted as required, or the circuit board default
values can be retained
9.8 Check CO2 content and adjust if necessary
(air–ratio adjustment)
Note:
Checking/adjustment of this value is required in
the following instances: replacement of gas
valve, conversion to or from Natural Gas/ LPG
or if incorrect combustion is suspected!
• Remove the case from the unit.
• Activate full gas rate mode by simultaneously pressing
the ”+” and ”–” buttons on the display system
(ecoMAX 800, fully open the hot water tap to maxi-
mum water flow rate).
• Wait at least five minutes, or until the unit has rea-
ched its operating temperature.
• Measure the level of CO
2
content at the exhaust–fume
test outlet (3) (Fig. 9.12). Check the reading against
the corresponding value in tab. 9.2.
• If the exhaust–fume setting requires adjustment,
remove the screw (4) and swivel the air suction pipe
(5) forwards through 90° (Fig. 9.12). DO NOT remove
the air suction pipe.
• Adjust the corresponding setting as required (see
Table 5.2, p. 39) by turning the screw (6) (see Fig. 9.13).
Natural gas:
Adjust in steps of no more than 1/8 of a turn,
and wait for each new value to stabilise (about
one minute).
LPG:
Adjust in small steps of no more than 1/16 of
a turn, and wait for each new value to stabilise
(about one minute).
Tab. 9.1 Values to be programmed in after installation of a new circuit board
Code
Meaning
Circuit board
Setting for
ecoMAX 600
Setting for
ecoMAX 800
setting
(default)
d.0
Heating system part load
Adjustable values in kW
45 kW
system-dep.
system-dep.
d.1
Heating system pump over run
1 - 60 min
5 min
system-dep.
system-dep.
d.2
Heating system max. off-period
1 - 60 min
20 min
system-dep.
system-dep.
d.71
Max. target value for heating-system
flow temperature
40 - 85 °C
82 °C
system-dep.
system-dep.
d.72
Hot-water pump over run
0 - 250 s
80 s
system-dep.
system-dep.
d.73
-15 K to +15 K
-9 K
Difference between warm start and
hot-water outlet target value
Displayed/Adjustable values
–
–
d.14
Pump speed
Set value for built-in pump
0 (= auto), 53, 60, 70, 85, 100 %
0 = (auto)
system-dep.
system-dep.
d.16
External CH pump
1, 2, 3, or 4
1
–
2
83 41 77_12 GB04.04.qxd 22.09.2004 12:34 Uhr Seite 54
