Checking The Refrigerant Pipes For Tightness; Installing The Heating Flow And Heating Return For The Domestic Hot Water Cylinder; Installing The Heating Circuit Connections; Installing A Drain On The Expansion Relief Valve - Vaillant VWL 57/5 IS Operating, Installation And Maintenance Instructions

4. Tighten the flare nut.
Heating Pipe diameter
output
3 to 5 kW 1/2 "
7 to 12 kW 5/8 "
5. Connect the liquid pipe (1). Use the product's flare nuts.
6. Tighten the flare nut.
Heating Pipe diameter
output
3 to 5 kW 1/4 "
7 to 12 kW 3/8 "
5.4

Checking the refrigerant pipes for tightness

1. Check the refrigerant pipes for tightness (see the install-
ation instructions for the outdoor unit).
2. Ensure that the heat insulation of the refrigerant pipes is
still sufficient after installation.
5.5 Installing the heating flow and heating return
for the domestic hot water cylinder
2
▶
Install the heating return (1) and the heating flow (2) for
the domestic hot water cylinder in accordance with the
relevant standards.
Connection symbols (→ Page 22)
5.6

Installing the heating circuit connections

1. Install the filling device on the product's heating return
using the seal provided.
0020257319_02 Hydraulic station Installation and maintenance instructions
Tightening torque
50 ... 60 Nm
65 ... 75 Nm
Tightening torque
15 ... 20 Nm
35 ... 45 Nm
2.
5.7
1
1.
2.
3.
6
6.1

Electrical installation 6

2
Install the return (1) and the flow (2) for the heating cir-
cuit in accordance with the relevant standards.
Connection symbols (→ Page 22)
Installing a drain on the expansion relief
valve
Install a drain hose (1) on the expansion relief valve.
Install the expansion relief valve hose in a frost-free
environment and ensure that its routing ends in an open
drain where it is then visible.
Ensure that escaping water does not endanger any
people or electronic components.
Electrical installation

Preparing the electrical installation

Danger!
Risk of death from electric shock as a res-
ult of an improper electrical connection!
An improper electrical connection may neg-
atively affect the operational safety of the
product and result in material damage or per-
sonal injury.
▶
Only carry out the electrical installation if
you are a trained competent person and
are qualified for this work.
1
1
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