Because you are calling with telo
equal to "tel12446", right?
So you need the "#" in front of that to make it a valid jQuery selector. Try
$("#" + telo).html(html);
And when calling the function, you'd be better off doing
... onclick="return Loadtel(12446,this.id);" ...
though that's not very important.
is obsolete. Just use
. So long as your function returns false (which it is *NOT* doing now!), that will work great.