Preventing Low Water Pressure; Flushing The Heating Installation For The First Time ("Cold"); Using Check Programmes; Check And Gas Setting - Vaillant ecoTEC plus VU 446/5-5 (H-GB) Installation And Maintenance Instructions Manual

7.7

Preventing low water pressure

To prevent damage to the heating installation that is caused
by low filling pressure, the product is fitted with a water
pressure sensor. If the filling pressure falls below 0.1 MPa
(1.0 bar), the product indicates low pressure by displaying a
flashing pressure value. If the filling pressure falls below 0.05
MPa (0.5 bar), the product switches off. The display shows
F.22.
▶
Top up the heating water to start the product up again.
The pressure value flashes on the display until a pressure of
0.11 MPa (1.1 bar) or higher has been reached.
▶
If you notice frequent drops in pressure, determine and
eliminate the cause.
The purging function is automatically active after a filling
procedure.
7.8 Flushing the heating installation for the first
time ("cold")
Applicability: Great Britain
OR Ireland
Note
The complete heating system must be flushed
at least twice: Once with cold water and once
with hot water in accordance with the following
instructions.
1. Check whether all thermostatic radiator valves and both
service valves on the product are open.
2. Connect a hose to the drain valve that is located at the
lowest position in the heating system.
3. Open the radiator valves and the drain valves so that
the water can drain quickly. Start at the next point in the
installation and open the purging valves on the radiators
so that the contaminated water can completely drain.
4. Close the drain cocks.
5. Refill the heating system with water.
6. Check that the expansion relief valve of the heating
system is functioning correctly by turning the handle
on the valve.
7. Check the pressure in the heating system and top up
with water if necessary.
8. Close the filling valve and the cold water tap.
7.9

Using check programmes

Menu → Installer level → Test programs → Check pro-
grams
You can activate various special functions in the product by
using various check programmes.
0020261389_02 ecoTEC plus Installation and maintenance instructions
Display Meaning
P.00 Purging check programme:
The internal pump is cyclically actuated.
The heating circuit and the domestic hot water circuit
are purged via the air separation system.
1 x : Start the heating circuit purging
( →
2 x ): Start the domestic hot water circuit
purging
→ ): Restart the heating circuit purging
3 x (
1 x (Cancel): End the purge programme
Note
The purging programme runs for 6.5 minutes per
circuit and then terminates.
P.01 Maximum load check programme:
After successful ignition, the product is operated at
maximum heat input if the flow rate in the heating
circuit permits this. Otherwise, the power is reduced
in order to adapt to the flow rate.
P.02 Minimum load check programme:
After successful ignition, the product is operated at
minimum heat input if the flow rate in the heating
circuit permits this. Otherwise, the product does not
ignite and it remains in waiting mode (status code
S.85).
Note
If the product is in error condition, you cannot start
any check programmes. You can detect an error
condition by the fault symbol shown in the left
bottom corner of the display. You must first reset.
To terminate the check programmes, you can select (Can-
cel) at any time; this does not apply for initial start-up, how-
ever. The purging cycle must be completely carried out once
so that the burner can ignite.
7.10

Check and gas setting

7.10.1 Checking the factory setting
Caution.
An incorrect gas type setting may cause
malfunctions or a reduction in the service
life of the product.
If the product design does not match the local
gas type, this may lead to malfunctions or to
some components wearing prematurely.
▶
Before you start up the product, compare
the gas type information on the data plate
with the gas type group available at the
installation site.
The product's combustion has been factory tested and is
preset for operation with the gas type indicated on the data
plate. In some supply areas, these settings may need to be
adjusted at the installation site.
Start-up 7
25