Replacing The Sensors - Grundfos MIXIT Installation And Operating Instructions Manual

21. Proceed with the startup procedure. See the installation and
operating instructions for the product.
Link to Installation and operating instructions
http://net.grundfos.com/qr/i/99513532

9.6 Replacing the sensors

WARNING
Pressurised system
Death or serious personal injury
‐
All valves must be closed to avoid liquid backflow.
‐
Fit the bracket screw and tighten it with a torque of 1.5
Nm.
The temperature sensor has a red sensor body, while the
flow sensor has a black sensor body.
You can replace both the temperature and the flow sensor of the
MIXIT unit. Do as follows:
Dismantling
1. Switch off the power supply.
2. Close the isolating valves on all three ports of the MIXIT unit.
3. Remove the insulating shells
4. Remove the terminal cover by loosening the two screws.
5. Loosen the cable gland of the sensor cable in question and
unscrew it from the control box. Make sure not to turn the
sensor cable at the same time.
6. Unplug the sensor cable from the terminal and gently pull the
sensor cable out of the control box.
7. Loosen the clamp
8. Carefully detach the control box.
9. Unscrew the bracket screw on the sensor in question and slide
the sensor bracket to the right and remove the bracket.
10. Hold the faulty sensor by its sides and move it gently from side
to side until the sensor comes off. Make sure to remove the
sensor sleeve from the valve housing.
Assembly
11. Clean the sensor hole with a clean piece of cloth, and make
sure that there are no particles in the sensor hole.
12. Fit the new sensor with the sensor cap, and gently push it home.
13. Fit the bracket by sliding it from the right to the left.
14. Mount the earth cable and flat connector
(only temperature sensor).
15. Fit the bracket screw and tighten it with a torque of 1.5 Nm.
16. Attach the control box, making sure that an intervention is made
between the stem and coupling.
17. Tighten the clamp with a torque of 3.5 ± 0.5 Nm.
18. Lead the sensor cable through the hole in the control box and
connect it to the terminal.
19. Fit and tighten the cable gland. Do not turn the sensor cable
while tightening the cable gland.
20. Fit the terminal cover and tighten the two screws with a torque
of 1.1 to 1.4 Nm.
Example:
48
1
Sensor placement on the MIXIT valve body
Pos. Description
1 Vortex Flow sensor Standard (VFS)
2 Integrated temperature sensor Standard (ITS2)
2