Start-Up; Maintenance; Frost Protection - Grundfos CR 2 Instrucciones De Instalación Y Funcionamiento

8. Start-up

Note: Do not start the pump until it has been filled with liquid and
vented.
Pay attention to the direction of the vent hole and
take care to ensure that the escaping water does not
cause injury to persons or damage to the motor or
other components.
In hot-water installations, special attention should be
paid to the risk of injury caused by scalding hot water.
Step
1
2
3
4
5
6
7
Action
Close the isolating valve on
the discharge side of the
pump and open the isolating
valve on the suction side.
Remove the priming plug from
the pump head and slowly fill
the pump with liquid.
Replace the priming plug and
tighten securely.
See the correct direction of ro-
tation of the pump on the mo-
tor fan cover.
Start the pump and check the
direction of rotation.
Vent the pump by means of
the vent valve in the pump
head. At the same time, open
the discharge isolating valve a
little.
Continue to vent the pump. At
the same time, open the dis-
charge isolating valve a little
more.
Close the vent valve when a
steady stream of liquid runs
out of it. Completely open the
discharge isolating valve.
CR 2 and 4,
CRN 2, 4, 8 and 16:
For these pumps, it is advisable to open the bypass valve during
start-up. The bypass valve connects the suction and discharge
sides of the pump, thus making the filling procedure easier. When
the operation is stable, the bypass valve can be closed. When
pumping liquids containing air, it is advisable to leave the bypass
valve open.
Fig. 7

9. Maintenance

Before starting work on the pump, make sure that all
power supplies to the pump have been switched off
and that they cannot be accidentally switched on.
Pump bearings and shaft seal are maintenance-free.
If the pump is to be drained for a long period of inactivity, remove
one of the coupling guards to inject a few drops of silicone oil on
the shaft between the pump head and the coupling. This will pre-
vent the shaft seal faces from sticking.
Motor bearings:
Motors which are not fitted with grease nipples are maintenance-
free.
Motors fitted with grease nipples should be lubricated with a high-
temperature lithium-based grease, see the instructions on the fan
cover.
In the case of seasonal operation (motor is idle for more than
6 months of the year), it is recommended to grease the motor
when the pump is taken out of operation.

10. Frost protection

Pumps which are not being used during periods of frost should be
drained to avoid damage.
Drain the pump by loosening the vent screw in the pump head
and by removing the drain plug from the base.
Care must be taken to ensure that the escaping water
does not cause injury to persons or damage to the
motor or other components.
In hot-water installations, special attention should be
paid to the risk of injury caused by scalding hot water.
Do not tighten the vent screw and replace the drain plug until the
pump is to be used again.
CR 2 and 4,
CRN 2, 4, 8 and 16:
Before replacing the drain plug in the base, screw the bypass
valve out against the stop, see fig. 7.
Fit the drain plug by tightening the large union nut followed by the
bypass valve.
Drain plug
Bypass valve
7