Vaillant ecoTEC plus Installation And Maintenance Instructions Manual page 35

9.6.9 Replacing the impeller sensor on the shift-
load cylinder
1. Close the hot water system stop valves and drain the
heat generator and shift-load cylinder on the hot water
side.
1
5
4
3
2. Remove the discharge pipe (1) from the expansion re-
lief valve on the heat generator.
3. Remove the plug from the impeller sensor.
4. Undo the screwed connections (2) and (3) on the angle
pieces (4) and (5).
5. Turn the impeller sensor slightly to the side and pull it
downwards to remove it from the casing.
6. Remove the pipe elbow from the impeller sensor.
7. Install the pipe elbow on the new impeller sensor and
use new seals for it.
8. Install the new impeller sensor in reverse order and use
new seals.
9. Connect the connection cable plug to the new impeller
sensor.
10. Reinstall the discharge pipe (1) and use new seals.
11. Fill and purge the heat generator and the shift-load
cylinder.
9.6.10 Replacing the PCB or display for the heat
generator
Note
If you only replace one component, when the
product is switched on, the new component ad-
opts the parameters that were previously set from
the component that was not replaced.
1. Open the electronics box. (→ Page 18)
2. Replace the PCB or display according to the assembly
and installation instructions supplied.
0020209593_01 ecoTEC plus Installation and maintenance instructions
3.
4.
9.6.11 Replacing the PCB and display for the heat
1.
2.
2
3.
4.
5.
6.
7.
8.
Troubleshooting 9
If you are replacing the PCB, remove the coding resist-
ance (1) (plug X24) from the old PCB and plug the plug
onto the new PCB.
Close the electronics box.
generator
Open the electronics box. (→ Page 18)
Replace the PCB and display according to the
assembly and installation instructions supplied.
Remove the coding resistance (1) (plug X24) from the
old PCB and plug the plug into the new PCB.
Close the electronics box.
Press the on/off button on the product. (→ Page 20)
◁
After switching on, the product switches directly to
the menu to select the language. The default lan-
guage setting is English.
Select the required language and confirm by pressing
.
◁
You are automatically taken to D.093 to set the
device specific number.
Set the correct value for the relevant product type in ac-
cordance with the table below and confirm by pressing
.
Product type number
938 (VUI GB 386/5‑5 A)
ecoTEC plus
◁
The electronics are now set to the product type and
the parameters of all diagnostics codes are set to
default settings.
◁
The installation assistant starts.
Make the system-specific settings.
1
1
17
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