Temporarily Setting Limp Home Mode; Cleaning The Outside Temperature Sensor; Changing The Batteries - Vaillant multiMATIC VRC 700f/4 Operating Instructions Manual

6 Troubleshooting
6.1

Temporarily setting limp home mode

If the fault message Restricted operation/ comfort pro-
tection Inactive appears on the display, the heat pump has
failed and the controller enters limp home mode. The auxili-
ary heater now supplies the heating installation with heating
energy. During installation, the competent person has restric-
ted the temperature for limp home mode. You can feel that
the hot water and heating are not becoming very hot.
While you wait for the competent person to come, you can
use the rotary knob to implement the following settings:
Inactive: The controller works in limp home mode; heating
and hot water at a moderately warm temperature
Heating: The auxiliary heater takes over heating mode; hot
heating, cold hot water
DHW: The auxiliary heater takes over domestic hot water
mode; hot water hot, heating cold
DHW+heat.: The auxiliary heater takes over heating and
domestic hot water mode; heating and hot water hot
The auxiliary heater is not as efficient as the heat pump,
meaning that using only the auxiliary heater to generate heat
is expensive.
If you want to implement settings on the controller, click
Back and the basic display appears on the display. After five
minutes of no operation, the fault message appears again in
the display.
6.2

Cleaning the outside temperature sensor

Caution.
Risk of material damage caused by un-
suitable cleaning agents.
▶
Do not use sprays, scouring agents, de-
tergents, solvents or cleaning agents that
contain chlorine.
▶
Clean the solar cell with a damp cloth and a little solvent-
free soap.
Note
After you have cleaned the solar cell, there is
a delay before the fault message disappears
because the battery has to be recharged first.
20
6.3

Changing the batteries

B
1. Remove the control from the unit mounting bracket as
shown in the figure.
B
2. Open the battery compartment as shown in the figure.
3. Always change all the batteries at the same time.
–
Only use LR06 batteries
–
Do not use rechargeable batteries
–
Do not combine the batteries with other battery
types
–
Do not combine new and used batteries
4. Insert the batteries, making sure that the poles are the
right way round.
5. Do not short-circuit the connection contacts.
6. Close the battery compartment.
Operating instructions multiMATIC 0020237615_01
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