Operation

Caution

1. Check for loose bolts before operation. Retighten the split plate mounting bolts, the rear casing support mounting bolts and the air vent-/drain-plate mounting bolts by the specified torque. See page 46 and 47 for detail.

2. When the pump keeps running in negative rotation, the pump breaks.

3. Closed-discharge operation should be within one minutes.

4. Make sure that a flow rate is always equal to or more than the minimum. The operation below the minimum flow can reduce the lubricant and cooling effect on the sliding parts. This could lead to failure.

Minimum flow

Model Motor poles 2P 4P MDW50 12m³/hr (200ℓ/min)12m³/hr (200ℓ/min) MDW80/100 60m³/hr (1000ℓ/min)12m³/hr (200ℓ/min)

Daily inspection

Conduct daily inspection to detect abnormality or determine if the pump should be dismantled or not. The operating condition can be checked by discharge pressure, suction pressure, a flow rate, current and voltage.

3. Shutdown

1. Slowly close a discharge valve. Quick closing by a solenoid valve may cause water hammer and damages the pump. Be sure to slowly close any discharge valve.

2. Switch off and stop the pump. Check that the pump stops smoothly. If the pump stops roughly, inspection is needed.

CAUTION

When leave the pump stopped for a long period, take a countermeasure against freezing for the prevention of freeze in the pump and piping. In case a blackout interrupts the pump operation, switch off the pump and close discharge valves.