The Zimbabwean Gardener Issue 12 Autumn 2015 High res | Page 23

Advertorial

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Pressure Tanks

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Varem

5 Quality E
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There is a common misconception that
pressure tanks are ‘booster tanks’, as in they
can boost your pressure in your system, or
that they work as storage tanks. That is not
the case.
The only thing that will pressurise your system is your pump,
whether it is for your house, your garden or even large
commercial setups. The pressure tank has a pressure switch
acting as a buffer and switches your pump on and off as
required. When the pressure gets to the pre-set maximum
pressure level, the pump turns off and turns on when the
pressure drops.
The pressure tanks from Varem are ‘bladder tanks’ or ‘precharged pressure tanks’. This means that they have a vinyl
bag inside the tank with pressurised air on the outside of
this bladder. The air is generally pre-set to a pressure of 2
bars. One of the main advantages to this system is that your
pressure tank can be a lot smaller than the older type of tank,
while maintaining the same working capacity. This is because
a non-pressurized tank needs to halve the amount of air in
the tank each time to double the pressure as shown in the
diagram. However, the problem is that the pump will have to
turn on when the pressure in the tank drops, thus increasing
the number of times you turn on the tank.
Whereas in a pressurised tank, you can use all 50 litres,
without losing pressure, before the pump needs to turn back
on. You are therefore reducing the number of times your
borehole motor or booster pump has to turn on/off, which
greatly increases the lifespan of your motor and pump. But
needless to say, there is a big saving to be had by opting for
the smaller size tank as well as reducing the wear and tear on
your pump.
The other advantage is that the water is completely contained
within the bladder. This prevents the tank from rusting away
as there is no contact between the water and metal. In the old
types of tanks, this rust will slowly start to flow into your water
system and clog your taps and geysers.

the water. In the Varem tanks, this does not occur, as there is
no direct contact between the air and the water.
In fact, the good quality bladders in the Varem tanks will last
years before they need replacing. And if the bladder should
rip, all that is needed is to replace the bladder.
Lastly the single inlet/outlet in the Varem Pressure tanks
means that fewer fittings are needed when installing these
tanks which make it easier and cheaper to install into an
existing system. The tank can be placed anywhere in the
system with just a single line going to it.
100L Varem

12.5L

GLENARA
cnr Samora Machel
Glenara
0772 187 421/2

25L

4 Bar
50L

4 Bar
2 Bar
1 Bar

50L

2 Bar

The older versions compress the air inside the tank by
pumping water into it, thus, becoming waterlogged every so
often. It becomes waterlogged when there is no longer any
air inside the tank or the air cushion becomes too small to be
efficient. The reason this happens is that the air dissolves into
the water as there is nothing separating the air cushion and

Visit any of our Driptech
branches to learn more about
saving water with dripline.

100L old type

www.driptech.co.zw
Avondale
19 Phillip Ave
Belgravia
0772 158 310/1

Southerton
18 Charing Cross
Workington
0772 143 996-8

Borrowdale
Pomona Shopping
Centre
04 882419/885387
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