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2. Operation (Starting)
1. Fully close discharge valve and fully open suction valve.
2. Fill liquid into pump
•
In case of flooded suction, confirm if suction valve is fully opened.
•
In case of suction lift, prime to fill liquid into suction piping.
3. Check rotating direction of motor.
•
Start motor momentarily (within a second) to check direction. Direction is shown on "arrow" mark on pump.
(Clockwise seen from motor fan side)
•
Also check if motor fan smoothly stops when switched off. If it does not stop smoothly, pump rotating parts may
be locked. Check the rotating parts.
4. Air vent operation
•
Before pump operation, vent the air in the pump.
•
Fully open the valve in air vent piping and repeat one second running for three to five times.
•
After the air vent running, fully close the discharge valve.
Note: In case air vent piping is not equipped, open the discharge valve to repeat momentary run several
times.
5. Starting pump
•
Start pump with discharge valve fully closed. (Maximum one minute)
•
Confirm that discharge pressure rises to shut-down pressure.
•
Gradually open discharge valve to get specified pressure (capacity).
Note: Pay attention to over-load caused by excessively opened valve.
Keep minimum allowable capacity to avoid seizure of bearing or rubbing parts.
3. Pump stopping
1. Slowly close the discharge valve
Quick closing of valve may cause water hammer and pump damage.
2. Switch off and stop the pump
Confirm if pump stops smoothly. If pump stops suddenly and not smoothly, inspection is needed.
3. When the pump is stopped for a long period, anti freezing measure must be taken so that the liquid can not be frozen
in the pump or piping.
Model
MDF-L422,423
Min. flow
20L/min
MDF-L425
50L/min
MDF-L250, 401
10L/min