Resol Grundfos Direct Sensors VFS Manuel Pour Le Technicien Habilité page 13

3 Mounting
VFS/VFD - Ga1/Ga2 - Gd1/Gd2
T / Q / GND / +5V
Note:
If the sensor has been correctly connected to RESOL controller, the
required grounding of the sensor is ensured. The grounding resistance
between pipe and sensor GND must be lower than 10 Ω.
4 Important note
ATTENTION If the empty solar thermal system is fi lled or fl ushed too
!
quickly, damage to the Grundfos Direct Sensors™ may
occur.
Î At the beginning of the fi lling / fl ushing process, open
the fi lling valve by max. 30 % in order to slow down
the fi lling / fl ushing fl ow!
As soon as the system is completely fi lled with fl uid, the fi lling valve can be
fully opened.
13
≥150 mm
max. 30%
max. 3 m!
≥75 mm
Note:
For the device to function faultlessly, the
system must be fl ushed and free of grit.