3.3 Operation
Operation
The VEN unit activates automatically whenever the
temperature drops below that set at the selector control
(
1). In a similar way, the VEN unit shuts down
automatically whenever the temperature exceeds that
set at the selector control (
1).
Overflow
During operation, the expansion of the water in the tank
as it heats up results in some hot water dripping from
the swiveling outlet. This is a normal procedure with
open tanks and tightening the tap valve assembly will
not prevent it occurring.
Frost protection
The water in the tank remains cold whenever frost-
protection mode is active (see figs. 3.1 and 3.2). A frost-
protection system nevertheless prevents the VEN unit
freezing up when it is connected to a water tank.
Indicator light
This indicator lamp (2) lights up to show that the pre-set
water temperature has not yet been reached. The
indicator light goes out once the pre-set temperature is
reached. The heating system shuts down.
3.4 Servicing and inspection
Vaillant VEN electric storage water heaters are designed
to require virtually no maintenance. All internal compo-
nents are protected from external influences. It is
sufficient just to wipe down the VEN unit occasionally
with a damp cloth – with a little water and mild
detergent if required.
Furring can occur with water of certain types and with
certain water temperatures and levels of consumption.
In the case of open appliances, this can lead to an
increase in pressure and – in extreme circumstances – to
irreparable damage to the appliance. Regular inspection
and descaling will prevent this happening. If the water
flow-rate drops noticeably, have the power-supply and
water-inlet components examined – and the VEN unit
descaled – by an authorised installer.
3.5 Troubleshooting
In the event of a fault occurring, disconnect the VEN
unit immediately by unplugging it from the mains power
supply. Have the fault rectified by an authorised service
installer only.
Danger!
Do not attempt to repair the appliance
yourself under any circumstances.
Figs. 3.3 / 3.4: Key
1 Temperature selector
2 Indicator light
VEN_004/0.eps
