The problemsBrass body - heavy
Not very fast acting (Some are)
Not water proof (They are not designed to be water proof, so will
need to be mounted in a dry chamber and so more pipe work is
required)
Must be 12 volt operated (This one is) but because of the low
voltage a higher current is required, which means a big transformer
On / Off They can only be on or off
Cost - this one is around £50
Solenoid valves are good for some uses, but not
for switching fountain jets, which is why we prefer to use
asynchronous pumps which have no valves, and can have a variable
output from 0 - 100%
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