The following pictures show two different air valve installations, one is a bore pump operated by Riverina Water just outside the racecourse (which you can see in the background) in Wagga Wagga (Series RBXb,16 Bar rated), this valve set up was demonstrated during the 2005 Pipes Wagga Wagga Field Day . The other is a sewerage pump station for Wagga Wagga City Council (Series RGX short band 3.8 bar rated).   

Example One – Riverina Water, Bore Pump 

 This is a good example of how a Ventomat air valve should be installed for a submersible / deep well pumping application. Firstly, a Series RBXb should be used. The Series RBXb has a spring on the top of the valve that holds the top / ‘Anti-Shock’ float in the closed position. This means that the outlet is reduced by approximately 35 times during high volume air release ie pump start up while still allowing full vacuum protection. This causes the air to be compressed when it is being released (due to the relatively small outlet orifice). This will cause backpressure that will slow the water velocity in the riser to an acceptable level so that no damaging pressure spikes will occur upon closure of the valve (basically using the pipeline as a surge tank).

A large or full diameter tee is also being used which will, in conjunction with the above set-up, create a separation point for the mixture of water and air that tends to get pumped up the riser upon pump start up. This will stop splashes of water hitting the lower floats of the air valve that will confuse the valve, thinking it is full of water, and closing it prematurely.

In summary the above set-up will ensure all air is released as quickly as possible without causing excessive pressure upon start up.

Note: an isolating valve should be installed below the air valve to enable the valve to be removed if necessary without having to shut the main down.

Example Two – Wagga Wagga City Council Sewerage Pumping Station 

 The above installation is sewage pump station about 5-6 Km’s out of town. This is a short pattern RGX air valve, this means it is shorter than the conventional 10 bar rated valve (approx 600mm in height). Pictured here is Len Kennedy from the council and Neil Mannix from AVK. They are standing next to a big bed of mulch that is used to remove any odour from inside the pump station. The air valve on the wall has below it a big white mark where the wall has been stained by the previous sewerage air valve, which leaked profusely. The Ventomat design overcame the problem in this instance by way of its long thin body, this design means only 2 metres head (20kPa) is required to effectively form an air pocket in the valve to keep sewage away from the working parts of the valve. With the previous design valve with a fatter body approximately 8 metres of head is required to form the air pocket. At this pump station there was not much pressure at times.

Ventomat air valves will be used on future applications around Wagga Wagga.

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