My kitchen sink won't drain. I've removed the trap to check for clogs but its clear. I suspect then that my drain vent is plugged. If so what is the best way to unplug it? I've been told to run a hose down the vent from the roof and flush it. But if I do that I'm wondering where the water and whatever is plugging it goes?
Thank you, Bonniel

Bonnie:

Your venting system is connected to the drain system. The only difference is that the pipe terminates to open air, which creates a way for the drain system risers and such to drain without sucking all the water out of the P-traps, connected to every plumbing appliance in your house, that prevent critters and smells from making their way into your house (the P trap is filled with 4" or so of water on the wall and drain side so no open air between your house and the main drain pipes). If there were no vent, the water traveling away from your sink would create a vaccuum behind it and siphon the water out of the P-traps.

Now that you know everything you could want to know about vents, the clog could should be down line from the drain. If the vent line is severely clogged, you would probably have dry or low water in the P traps due to the siphoning mentioned above. This is not a perfect test, since if the vent clog is weak, then there is a chance that the P traps could still be wet.

So if you are absolutely sure that the vent is clogged, then purge away, but keep in mind that if you pour a bunch of water down the vent and it doesn't dislodge the clog, water will find it's own level eventually, which could end up being higher than your sinks in your house, so keep an eye on the sinks in your house while doing this to make sure that you're not overrunning the house with water out of the sinks. Also take care not to fall off your roof while doing this.

Best and safest of all is to hire a plumber.

The best way is to use snake from the kitchen roof vent, Put out enough cable to reach the base and 20 feet more, Flush out after with a garden hose down the vent,good luck.

John

I agree with afaroo's directions on rodding a vent, they are perfect. However this is not your problem. If your vent is clogged the sink will still drain but may chug and burp, you could even get sewer gas if the trap was to be siphoned. It would still drain. If you really aren't draining you need to remove the trap and rod into the lateral drain going into the wall. You will hit a 90 elbow about 8" in so you need to use a small 1/4" snake. Brad is correct, the clog is downstream of the trap.

95% of times it is your drain that is clogged up. Not vent. Concentrate on drain, snake it several times, run lots of hot water each time you use garbage disposer - and you should be just fine...

Thanks to all who tried to help with my clogged drain. I've snaked it several times and run hot water into it. I'm getting a black oily stuff out of drain but its still clogged. It will drain once and then when I put water in it again it plugs. What the heck is going on?

thanks to all who tried to help with my clogged drain. I've snaked it several times and run hot water into it. I'm getting a black oily stuff out of drain but its still clogged. it will drain once and then when I put water in it again it plugs. What the heck is going on?
Did you remove the "J" bend and snake up into the wall?(see image). If that's what you did then they snake was so small the grease and goop simply closed in behind it and you still have a clog. Try this, Go back in with a larger snake or one with a auger on the end. Run your snake in at least 6 feet. Bring the snake back and replace the trap. Now boil naq few large pans of water and fill up one side of the sink with the hotest water you can make. Pull the stopper and let it all go. The boiling water will melt the grease and the head pressure from the kitchen sink will tend to force the mess out into the main. Good luck, Tom