Starting The Pump The First Time; Operating Parameters; Freeze Protection - Grundfos CR Series Installation And Operation Manual

Starting the Pump
the First Time
Priming
To prime the pump in a closed system or an open system where the water
source is above the pump, close the pump isolation valve(s) and open the
priming plug on the pump head. See Figures 5A and 5B. Gradually open the
isolation valve in the suction line until a steady stream of airless water runs
out the priming port. Close the plug and securely tighten. Completely open
the isolation valves.
In open systems where the water level is below the pump inlet, the
suction pipe and pump must be filled and vented of air before starting the pump. Close the discharge
isolation valve and remove the priming plug. Pour water through the priming hole until the suction pipe and
pump are completely filled with water. If the suction pipe does not slope downward from the pump toward
the water level, the air must be purged while being filled. Replace the priming plug and securely tighten.
1. Switch power off.
2. Check to make sure the pump has been filled and vented.
3. Remove the coupling guard and rotate the pump shaft by hand to be certain it turns freely.
4. Verify that the electrical connections are in accordance with the wiring diagram on the motor.
5. Switch the power on and observe the direction of rotation. When viewed from the top, the pump should rotate counter-clockwise
(clockwise for CRN-SF).
6. To reverse the direction of rotation, first switch OFF the supply power.
7. On three-phase motors, interchange any two power leads at the load side of the starter. On single-phase motors, see connection
diagram on nameplate. Change wiring as required.
8. Switch on the power and again check for proper motor rotation. Once rotation has been verified, switch off power again. Do not
attempt to reinstall the coupling guards with the motor energized. Replace the coupling guard if the rotation is correct. After guards
are in place the power can be reapplied.
NOTE: Motors should not be run unloaded or uncoupled from
the pump at any time; damage to the motor bearings will occur.
REMINDER: Do not start the pump before priming or venting the pump.
Never operate the pump dry.

Operating Parameters

CR multi-stage centrifugal pumps installed in accordance with these instructions and sized for correct performance will operate efficiently and
provide years of service. The pumps are water-lubricated and do not require any external lubrication or inspection. The motors will require
periodic lubrication as noted in the following Maintenance Section.
Under no circumstances should the pump be operated for any prolonged periods of time without flow through the pump. This can result in motor
and pump damage due to overheating. A properly sized relief valve should be installed to allow sufficient water to circulate through the pump to
provide adequate cooling and lubricaton of the pump bearings and seals.
Pump cycling
Pump cycling should be checked to ensure the pump is not starting more than:
20 times per hour on 1/3 to 5 HP models
15 times per hour on 7 1/2 to 15 HP models
10 times per hour on 20 to 60 HP models
Rapid cycling is a major cause of premature motor failure due to increased heat build-up in the motor. If necessary, adjust controls to reduce the
frequency of starts and stops.
Boiler-feed installations
If the pump is being used as a boiler-feed pump, make sure the pump is capable of supplying sufficient water throughout its entire evaporation and
pressure ranges. Where modulating control valves are used, a bypass around the pump must be installed to ensure pump lubrication (see "Minimum
Continuous Duty Flow Rates").

Freeze Protection

If the pump is installed in an area where freezing could occur, the pump and system should be drained during freezing temperatures to avoid
damage. To drain the pump, close the isolation valves, remove the priming plug and drain plug at the base of the pump. Do not replace the plugs until
the pump is to be used again. Always replace the drain plug with the original or exact replacement. Do not replace with a standard plug. Internal recir-
culation will occur, reducing the output pressure and flow.
8
Figure 5a
Priming Vent Plug
CR(I)(N) 1s, 1, 3, 5, 10, 15, 20
CR(X)(N)(T) 2, 4, 8, 16
Suction
Drain Plug
Figure 5b
Discharge