House is 14 yrs. Old. Outdoor faucet to attach hose has a round thing on top, which allows water to leak out when water is turned on. Losing at least 25% of water entering the hose. How do I replace or repair this. The round thing on top of spigot looks to be some type of a pressure valve. Turning it does not tighten the round thing. Tried putting silicone sealant around the area where spigot comes out of brick wall and all around the round thing. Does not work still leaking.

How do I repair or replace. Any pictures to help me? I'm a 58 yr old woman who knows nothing about plumbing.

In believe "that round thing" might be the bonnet packing nut, (see image)
If the water sprays out around the stem this is the nut you'll have to snug up. Push the packing nut down until the threads engage. Now open the valve up a bit until watercomes out out around the stem. Snug the packing nut up until the water stops. CAREFUL! Don't overtighten. Why did you seal where it came out of the wall? Another leak? Good luck, Tom

Mrs. Fixitmese...

I'm actually going to bet that it is the VACUUM BREAKER you are talking about... see image (most of this will be hidden in the wall).

Sometimes, if you can find an exact replacement then you can remove the old vacuum breaker and replace it with a new one. Sometimes, you simply can't find an exact replacement and therefore the whole valve will need to be replaced.

Let me know if me or Tom is on the right track

MARK

Mark's most likely correct, (he usually is) He put up a frest free "Yankee" type vacuum breaker. Here's how ours look in Florida. Regards, Tom

"Yankee vacuum breaker"... LOL