Vaillant VUW 246/5-3 (H-GB), Installation And Maintenance Instructions Manual

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Installation and maintenance instructions ecoTEC pro 0020244995_04
7 Installation
7.1 Installation requirements
7.1.1 Information on the gas group
In the as-supplied condition, the product is preset for opera-
tion with the gas group indicated on the data plate.
7.1.2 Purging the liquid gas tank
If the liquid gas tank is not purged properly, this may result in
ignition problems.
▶
Ensure that the liquid gas tank has been purged properly
before installing the product.
▶
If required, contact the filler or the liquid gas supplier.
7.1.3 Using the correct gas type
Using the incorrect gas type may cause fault shutdowns in
the product. Ignition and combustion noise may occur in the
product.
▶
Only use the gas type listed on the data plate.
7.1.4 Preparing for installation
1. Make sure that the existing gas meter is capable of
passing the rate of gas supply required.
2. Consider the maximum heat output given in DHW
mode.
3. Install a system separator (to be provided on-site) dir-
ectly on the cold water connection for the combi boiler.
4. Install the following components:
–
Draining cocks at the lowest points in the heating
installation (
→
current version of "BS 2879")
–
A stopcock on the cold water connection
–
A stopcock in the gas pipe
5. Check that the volumetric capacity of the expansion
vessel is sufficient for the system volume.
Condition : The volume of the installed expansion vessel is insufficient
▶
Install an additional expansion vessel, connected as
close to the product as possible, in the heating return.
Condition : External expansion vessel installed and warm start active
▶
Install a non-return valve in the product outlet (heating
flow) or decommission the internal expansion vessel
in order to prevent the warm start function from being
increasingly activated due to backflow.
6. Install the connection pipes such that they are free from
mechanical stress.
7. If you use non-diffusion-tight plastic pipes in the heating
installation, ensure that no air gets into the heat gener-
ator circuit.
8. Only solder connectors if the connectors are not yet
screwed to the service valves.
9. Only bend connection pipes if they have not yet been
connected to the product.
10. Flush the heating installation thoroughly before
installing the product.
11. Check the leak-tightness of the gas valve assembly
using a pressure of
≤
11 kPa (110 mbar).
7.1.5 Descaling the water
Scale deposition increases as the water temperature in-
creases.
▶
Descale the water as required.
7.2 Installing the gas connection
1. Install the gas pipe in accordance with the recognised
rules of technology.
2. Connect the product to the gas line as shown in ac-
cordance with the recognised rules of good engineer-
ing practice.
3. Remove the residues from the gas line by blowing
through the gas line beforehand.
4. Purge the gas line before start-up.
7.3 Checking the gas line for leak-tightness
▶
Check the entire gas line properly for leak-tightness.
7.4 Installing the hot and cold water connection
1. Make the water connections as shown in accordance
with the relevant standards.