Can anyone tell me if the small threaded opening on my shut-off valve is for draining the water line in the fall ? We just purchased a home which has a pole buliding 100' away from our house. The pole building is sits on lower ground than our house.
There is a 3/4" shut-off valve inside the pole bulding. On the SIDE of the valve there is a small cap. I took the cap off. ( About the size of a valve stem on a tire.) It looks like an air compressor could be hooked up to the small fitting. Does this sound right to anyone ? The line which is buried to the pole buliding is black plastic 3/4" or 1" . I hope it didn't crack last winter. We bought the house in October and I didn't do anything with it. I opened the faucet at the pole building and closed the feed valve in the house basement in Nov or Dec of last year. Any ideas about this small threaded hole/ cap ?
Thanks.....Tony.

 

It's an air bleeder. This type valve was commonly used on outside faucets and in the winter, when they were shut off, the water was still in the faucet and froze. The air bleed allowed air in so the faucet could drain.

 

What you have is called a stop and waste valve, the port that you are talking about should drain the up-stream pipe from the valve. It should have a arrow on it; if the arrow points to the pressure side the valve it is put in backwards and it won't do anything. These valves were also used where you wanted to drain water out of a segment of pipe without shutting off the whole house. Hope this helps.

 

Thanks for the replies.....I get it now. I took the cap off and
the remaining water in the line drained out. Thanks for the great website.....It's very helpful. Tony.

 

Hmmm, I didn't know that there were 49er fans in Green Bay.

Interesting.