Diagnosis Codes; A Caution - Vaillant ecoTEC VU 656/4 Installation And Maintenance Instructions Manual

9.1.2

Diagnosis codes

In the diagnosis mode, you can change certain
parameters or display more information.
The diagnosis information is divided into two diagnosis
nd
levels. The 2 diagnosis level can be reached only after
entering a password.
a Caution!
The access to the 2
be used by a qualified heating engineer.
st
1 diagnosis level
• Push the "i" and "+" buttons simultaneously.
The display shows "d.0".
• Scroll to the desired diagnosis number on the 1
diagnosis level with the "+" or "–" buttons (see
Table 9.2).
• Push the "i" button
The display shows the relevant diagnosis information.
• If necessary, use the "+" or "–" keys to change the
value (display flashes).
• Save the new value by holding the "i" button pressed
for about 5 seconds until the display stops flashing.
You can finish the diagnosis mode as follows:
• Push the "i" and "+" buttons simultaneously or
• Do not push any buttons for about 4 minutes.
The current heating flow temperature or the current
water pressure of the heating installation reappears in
the display.
Installation and maintenance instructions ecoTEC 0020029173_01
nd
diagnosis level may only
st
Troubleshooting 9
45