Checking The Level Sensor - Grundfos LC 109 Service Kit Instructions

Installing pressure tube and tightening
Fig. 8
screw cap
7. Pull the cable of the new sensor through the PG
cable entry and tighten the PG cable entry.
8. Connect the cable to the connector block
according to the table below.
Controller 11 12 22
Sensor 5 1 2
Colour Grey White Green Yellow Pink Brown Blue
9. Connect the pressure hose between level
converter and screw cap.
– The pressure hose must be routed rising
towards the controller to avoid condensation in
the hose.
– Connect the pressure hose between the
pressure tube in the tank and the bulk head
fitting in the converter box. The pressure hose
must be inserted up to the stop. Insert
approximately 18 mm. Otherwise there is a
risk of leakage resulting in pressure loss,
inaccurate level detection and malfunction of
the system.
– Excessive lengths of pressure hose should be
cut away. The pressure hose must not be
kinked.
– The connection must be air tight to ensure
reliable operation.
Connection
32 42 L N
3 4 L N
Fitting hose to level converter
Fig. 9
Fitting hose to pressure tube
Fig. 10
10. Close the LC 109, LCD 109 or LCD 110
controller.
11. Reconnect the controller to mains and switch it
on.
12. Flush the tank and check the lifting station for
proper operation.

7.1 Checking the level sensor

To check the function of the level sensor and to verify
that the sensor is operating within the defined levels,
proceed as follows:
1. Remove the pressure tube from the tank again.
2. Fill a bucket with water.
3. Make marks on the tube according to the table
below.
4. Slowly immerse the tube into the water and
watch the reaction of the LEDs when the water
level reaches the various marks. The LEDs on
the LC/LCD control unit, CU 211 / CU 214, should
light up according to the water level in the bucket.
7