Instructions

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.