When I turned my faucet on it leaks from the top - do I have to replace the faucet?
not alot of info? but if it has a nut on front? and leaks there you have a packing nut. It can usually be snugged up to stop a leak. If it is coming from in wall or elsewhere these taps extend into the wall 12-14" and are called freeze valves. If it is leaking it likely have split in winter and leaks now or some other issue and yes it needs to be replaced. Work will need to done from outside and in ceiling the inside.
Cheers
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