Installation Tips; Installation With Ball Valve And Non-Return Valve; Installation Of The Inlet Line; Installation With Pressure-Relief Valve - Grundfos DMX 221 Installations- Und Bedienungsanleitung

2.1.2 Installation tips

The drawing shows an example of an optimum installation. The following subsections describe
various components and when they should be used.
Pos.
1
2
3
4
5
6
7
8
9
10
11
p1
p2

2.1.2.1 Installation with ball valve and non-return valve

For easy deaeration of the dosing head, we recommend that you install a ball valve (12) with a
bypass line immediately after the outlet valve.
In order to prevent backflow in the outlet line and to simplify startup, we recommend that you in-
stall a non-return valve (13) in the outlet line.
12

2.1.2.2 Installation of the inlet line

When you install the inlet line, observe the following points:
• Keep the inlet line as short as possible. Avoid tangling.
• Use swept bends instead of elbows.
• Always run the inlet line up towards the inlet valve.
• Avoid loops. Loops may cause air bubbles.
8
2
3
1
6
4
Component
Dosing tank
Electric mixer
Graduated cylinder
Pulsation damper, inlet side
Dosing pump
Pressure relief valve
Pressure loading valve
Pulsation damper, outlet side
Measuring glass
Injection unit
Isolating valve
Pressure at the inlet valve
Pressure at the outlet valve
13
9
10
7
5
p2
p1
11
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