Want to add an air vent to a water line

[Mortimer Schnerd, RN]

Here's the deal: I just got through replacing a segment of copper pipe under my rear deck that had split over the winter. The line originates under the house where it doesn't freeze and there is a valve under there to shut off the water for the winter. The problem is that the outside outlet really isn't the lowest part of the line and so water collects in the line even when the inside valve is closed. Then when it freezes, the pipe splits outside under the deck.

I was thinking of some sort of tee/valve arrangement that would allow me to blow compressed air in that would force any residual water out of the line. Anybody have any ideas? I'm open to pretty much anything... I'm just tired of crawling under there to repair splits in the line two out of every three years.

[charlie]

can you put a T & valve in the low point, or a T with a longer hose with a valve at the far end, so that you just have to open it up to drain it? or are there multiple low points?

[Mortimer Schnerd, RN]

I have the ability to solder in whatever I want. Unfortunately the run looks pretty level to me and I don't have a good way to reposition it lower because it has to penetrate the foundation as it is. I don't want to punch more holes in the house if I can avoid it.

What I'd really like to do is be able to plug in an air line in some way to the pipe under the house just downstream of the inside shutoff. Then I could blow out the water left in the line no matter what.

My problem is visualizing what I need to accomplish this. Don't they do this sort of thing with campers and trailers when they winterize them?

[charlie]

think sprinkler lines. you probably can do this with a t, a long hose, a valve, and a leaf blower or shopvac.

[Charlie Bress]

I would put in a tee. Then get a cap to go on the open end of the tee and finally a shrader valve go into the cap. Put the valve on the cap first then attache the cap to the tee. Now you have a fitting that any compressor will inflate tires will allow you to pump air into the pipe. Keeping the air where you want it depends on the geometries of the installation you are working with.

Charlie

[DT]

Is the shutoff valve at the lowest point? They make shutoff valves with bleed ports just for this purpose. Place the valve in the line so the bleed port is on the downstream side. Shut off the valve and open the bleed (it's a small knurled knob) to drain the water. Leave it off until next spring if you want to.

[Chuck (in SC)]

"under the house where it doesn't freeze"... Is this crawl space? If it is.. I'd re route the line to exit somewhere other than under the deck.. so that you only have the hose bib sticking out which is then easy to protect. Anything to avoid having to crawl under the house that often.. And if the current location of the valve/bib is really a "great" place.. plumb in a easier to drain valve. Being in CLT, just putting a shutoff "t" valve with bleeder/ drain screw in place of bib.. wouldn't freeze on outside with a winter cover over it like for hose connection... would look odd when sold later on.. Chuck from Carowings

[Don Young]

The easiest solution is to get a Schrader (tire type) valve adapter which will connect to the outside faucet. These are available where camper and RV stuff is sold. Shut off the water and pressurize the line with air, not over about 60 PSI. Close the faucet, remove the adapter, and open the faucet. Repeat as necessary until all of the water is blown out. This may leave some water in the line if the cutoff is in a low point but generally works okay.

If there are other faucets downstream of the cutoff, you can blow the air into one and the water out the other. Or you can add a connection for the air at the cutoff.

Don Young

[businessman]

Since you mentioned this, they actually make straight couplers with bleeders on them. You can put that anywhere (at a low point).

Another thought, I heard that PEX dont break when it freezes. You could just run the PEX from the valve (under the house) to your outside spigot. Everything under the porch, exposed to the weather, would be PEX. Of course the spigot itself could still freeze.

[businessman]

I agree with others to put a tee at the lowest point. Then put a brass plug in it. Or put the tee and plug whereever you want, and stick your air nozzle in it. Of course there needs to be an outlet such as a valve for the water to come out. You said the pipe looks level, but use a level. If a half inch pipe is off by 1/8" per foot, after 4 feet, the pipe is filled with water. The location of the splits should tell you where the low spot is.