Well don't bugger up the head of the screw with the wrong tool for a start.
If the head is proud try clamping some moles on it and gently ease it in the
correct direction and back a few times.
Brian

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This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

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"Sarah" m wrote in
message oupdirect.com...
I live in a hard water area and so have to install a combo care scale
inhibitor once a year. I am a month late but have finally got round to it.
I
went to unscrew the top of the inhibitor with a variety of good
screwdrivers.
They fit in but the screw won't budge. I think the phosphates have
overflow
and jammed it tight. Any ideas for how to unclog it so I can actually
unscrew
it to change it?
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