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TECHNICAL
This issue Patrick looks at another valve in the series
By Patrick Gordon of Calafrica ( technical @ calafrica . co . za )
Q – How does an Automatic Air Release Valve work ?
During the daily use of our plumbing systems air can be trapped in various places . Normally air percolates to the highest places in the pipe system . When we use our taps , we will notice the presence of air in the system by a spluttering when the taps / mixers are used . This can be very annoying . By fitting an Air Release Valve this phenomenon can be prevented without us having to do anything extra .
Installations like solar heating systems are more prone to trapping air . For installations like that , the heat factor must be considered and a valve with a suitable temperature rating should be selected .
For any further information regarding this topic please feel free to contact Patrick Gordon on + 27 ( 0 ) 83 303 1437 . PA
“ Because air is lighter than water ..”
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Calafrica
So how does it work ? [ Please note that the image has numbers which are not part of the image ]
The valve must be installed in a vertical position at the highest point of that part of the system . The valve consists of a chamber that contains a float ( 1 ) attached to a needle valve ( 2 ). The weight of the float would normally keep the needle valve in the open position . Because air is lighter than water the air will go to the highest point , where the valve is fitted , and escape via the open needle valve . As the air escapes the water level in the system will rise and start to fill the chamber of the Air Release Valve . Because the float is buoyant the water will lift it and cause the needle valve to close . When this happens the seal on the needle valve seat is forced closed and will prevent the water from escaping . If any other air finds its way to the top of that part of the plumbing system , the float will again open the needle valve and allow the air to escape .
www . plumbingafrica . co . za @ plumbingonline @ plumbingonline @ PlumbingAfricaOnline June 2023 Volume 29 I Number 4