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Section 4 Installation, Commissioning and Routine Maintenance
Final checks before commissioning
1. Re-check all equipment for any accidental damage caused during installation.
2. Carry out the Precharging and Venting procedures described next.
Pressure Vessel Precharging
Before commissioning starts the precharge of the pressure vessels should be
checked.
On variable speed systems the precharge air pressure for vessels should be 90% of
the maximum pressure generated by the pump in the pipework system
e.g: If the max. pressure generated by the pump in a system is 6 bar.
This will require a pre-charge pressure of 6 x 90% = 5.4 bar.
Refer to the following table:
Required Pressure
Precharge Pressure
Fig. 4-1 Pump PreCharge Pressure Calculator
To verify the precharge pressure.
1. First check that the expansion or pressure vessel(s) are totally drained of water,
and that the system is switched off and no electrical parts are live.
2. Locate the charging valve on each vessel, accessed by removing the plastic
cover on the top of the vessel.
3. Connect a portable pressure gauge with a measuring range compatible with the
expected pressures in your application, which has a flexible hose and Schradertype connector to the charging valve.
4. Check the pre-charge pressure above the diaphragm in each pressure vessel
[Accumulator]. correspond to criteria given in the text above.
5. If necessary, release or add additional air to correct.
Venting Pumps
It is important to bleed all air from the pump body before initial start-up.
Procedure for flooded suction
Flooded Suction is defined as the condition where there is positive pressure on the
suction (inlet) side of the pump(s) as is the case where the storage tank water level
is at the same or higher level than the pump bleed point.
This procedure should be carried out individually for each pump in the Pumpset.
1. Close any valve on the discharge manifold outlet to the system.
2. Open all valves on the suction (inlet) side of the pump.
VG
Iss.4 - Aug 2013
31