Data Sheet

Table Of Contents
8 Using the product
13
2
Take a photo of the QR code of the
testo Smart App and press
[Menu/Enter] to confirm.
-
The measurement menu is displayed.
8 Using the product
8.1 Preparing for measurement
8.1.1 Operating the valve positioners
With respect to the refrigerant path, the digital manifold behaves just like a
conventional four-way manifold (only applies to the testo 557s): The passages
are opened by opening the valves. The applied pressure is measured with the
valves closed and the valves opened.
-
Open the valve: Turn valve positioner anticlockwise.
-
Close the valve: Turn valve positioner clockwise.
WARNING
Valve positioner tightened too tightly.
Damage to the PTFE seal (1).
Mechanical deformation of the valve
piston (2) leading to the PTFE seal (1)
falling out.
Damage to the thread of the threaded
spindle (3) and the valve screw (4).
Broken valve knob (5).
Only tighten the valve positioner hand-tight.
Do not use any tools to tighten the valve
positioners.