Purging The Heating System; Flushing The System For The First Time ("Cold"); Avoiding Low Water Pressure; Fill And Purge The Hot Water System - Vaillant ecoTEC pro Installation And Maintenance Instructions Manual

If the water pressure in the heating system is
i
too low, the display switches between fault mes-
sage F.22 and the display of the current pressure
when the boiler is switched on.
> Purge the lowest radiator until water flows out of the
purging valve without bubbles.
> Purge all other radiators until the entire heating system
has been filled with water. Close all purging valves.
> Use the display to monitor the rising filling pressure in
the heating installation.
> Top up with water until the pressure gauge display is in
the middle of the grey area and the required filling pres-
sure appears on the display.
> After filling, close the stop valve at the filling line and the
cold water valve.
> Check all connections and the entire system for leaks.

10.5.2 Purging the heating system

> To purge the heating installation, select test program
P.00 (¬ section 10.2).
The boiler does not start up, the internal pump operates
intermittently and, as an option, purges the heating circuit
or the hot water circuit. The display shows the filling pres-
sure of the heating installation.
> The filling pressure of the heating system must not fall
below 0.08 MPa (0.8 bar) when purging is in progress as,
otherwise, this will not be carried out properly.
The test program P.00 runs for 7.5 minutes per circuit.
At the end of the filling procedure, the filling pressure of
the heating installation should be at least 0.02 MPa
(0.2 bar) above the counterpressure of the expansion vessel
(P ³ P + 0.02 MPa (0.2 bar)).
Installation Exp
> If there is still too much air in the heating installation at
the end of test program P.00, repeat the test program.
> Check all connections for leaks.
10.5.3 Flushing the system for the first time
("cold")
The entire heating system must be flushed
i
through completely at least twice: once cold and
once hot, in accordance with the following
instructions.
> Check whether all thermostatic radiator valves and both
service valves on the boiler are open.
> Connect a hose to the drain valve that is located at the
lowest position in the heating system.
> Open the drain cocks and all the purging valves on the
radiators so that the water flows quickly and completely
out of the heating system and the boiler, in order to
Installation and maintenance instructions ecoTEC pro 0020129672_03
remove the contamination caused during installation out
of the heating system before the boiler is started up.
> Close the drain cocks.
> Refill the heating system with water, as described in
(¬ section 10.5).
> Check that the expansion relief valve of the heating sys-
tem is functioning correctly by turning the handle on the
valve.
> Check the pressure in the heating system and top up
with water if necessary.
> Close the filling valve and the cold water valve.
10.6

Avoiding low water pressure

To prevent damage to the heating installation caused by
low water pressure, the ecoTEC pro is fitted with a water
pressure sensor.
If the water pressure falls below 0.08 MPa (0.8 bar), the
boiler indicates low pressure by displaying a flashing pres-
sure value.
If the water pressure falls below 0.05 MPa (0.5 bar), the
boiler switches off.
The fault message F.22 appears in the display.
> Top up the water and switch the boiler on again.
A flashing pressure value appears on the display until a
pressure of 1.1 bar or higher has been reached.
If you notice frequent drops in pressure, then
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determine and eliminate the cause, i.e water
leaks in the system. Failure to do so along with
frequent topping up will result in system corro-
sion and subsequent failures.
10.7

Fill and purge the hot water system

> Open the cold water stop valve on the boiler.
> Fill the hot water system by opening all the hot water
draw-off points until water comes out.
As soon as water comes out of all the hot water draw-off
points, the hot water circuit is filled completely and also
purged.
10.8

Filling the condensate trap

Danger!
a
Risk of poisoning from escaping flue gas!
An empty or insufficiently filled condensate
trap may allow flue gas to escape into the
room air.
> Fill the condensate trap with water
before starting up the boiler.
Commissioning 10
33