Airlock in kitchen waste pipes

[ivorchas]

The water from my kitchen sinks drains very slowly . I have cleaned trap and know pipes are clear , so suspect an airlock The two sinks and dishwasher connect to the one fitting and the waste outlet from the trap runs horizontal for approx. 12 " then drops 12" before going through house wall where it connected to a 'T' connection . Down to main drain and up to vent with loose cap . I suspect the open part of 'T' connection was vent for the system . I ignorantly replaced the 'T' connection with a 90 elbow . Can I drill a hole in the elbow to restore the venting . If so , how do I prevent water spouting out of the hole ? Alternatively should the hole be drilled near the trap at the highest point of the pipework ? Again , how do I prevent watrr spouting out . All connections glued so difficult to replace . Would appreciate some advice .

Moved from CPUs.
admin allisolm

 

[deadlyapp]

No, you cannot drill holes wherever you want to try to get venting. There's a reason why it vents out the roofwork.

You may want to look into an air admittance valve to put under your sink if that is the only place where you're getting an issue and in fact it is the vent. You can also snake the vent to make sure it isn't clogged but it sounds like you may have gotten rid of the vent.

Pictures of your pipe work would be interesting.

 

[Greenman]

The water from my kitchen sinks drains very slowly . I have cleaned trap and know pipes are clear , so suspect an airlock The two sinks and dishwasher connect to the one fitting and the waste outlet from the trap runs horizontal for approx. 12 " then drops 12" before going through house wall where it connected to a 'T' connection . Down to main drain and up to vent with loose cap . I suspect the open part of 'T' connection was vent for the system . I ignorantly replaced the 'T' connection with a 90 elbow . Can I drill a hole in the elbow to restore the venting . If so , how do I prevent water spouting out of the hole ? Alternatively should the hole be drilled near the trap at the highest point of the pipework ? Again , how do I prevent watrr spouting out . All connections glued so difficult to replace . Would appreciate some advice .

Moved from CPUs.
admin allisolm

Since you clearly have no idea how plumbing works or what building code is, I recommend that you hire a plumber.
FYI, in 47 years of remodeling I have never once seen a waste line "air lock". Actually, I've never even heard of a waste line air locking.

 

[deadlyapp]

Since you clearly have no idea how plumbing works or what building code is, I recommend that you hire a plumber.
FYI, in 47 years of remodeling I have never once seen a waste line "air lock". Actually, I've never even heard of a waste line air locking.

It sounds like he didn't like an extra pipe so he just chopped it off. Probably his vent, but who knows without pictures / diagrams

 

[Greenman]

It sounds like he didn't like an extra pipe so he just chopped it off. Probably his vent, but who knows without pictures / diagrams

And the lack of a vent could cause the problem he's having, so the next obvious solution is drilling holes in his plumbing.

 

[ivorchas]

Thanks for your reply deadlyapp . You confirmed my thoughts , but I wanted reassurance that drilling was incorrect .All that I did was to replace the outside pipework . I attach photos of inside and outside pipes .The inside was as left by plumber who installed kitchen some years ago . And Greenman I did NOT cut off a pipe ( I do have some commonsense, but you are correct , I do have VERY basic knowledge ). I was told by a plumber that the problem was most likely an airlock .i
i HAVE CONSULTED A PLUMBER AND HE HAS SUGGESTED TO TIDY UP PIPES UNDER SINK , TO TAKE PIPE FROM TRAP STRAIGHT THROUGH WALL TO DRAIN AND DISPENSE WITH OTHER PIPES AND GET RID OF THE MANY BENDS . i WOULD VALUE A SECOND OPINION .

 

[Scarpozzi]

Normally, the sink trap empties into the wall and is introduced to a tee that vents to the roof (as stated before in this thread). That vent allows air to exit because it would have to gurgle through the trap otherwise to vent and allow the pipes to drain. If your sink is within 6' of the outside pipes, you could potentially add a vent there and it should still work, but it can't be too far below the sink or it would create the air lock you were describing if enough water got between the vent and the trap (which is why the vent should always be above the trap and no less than 6' away).

Did the pipes ever drain efficiently? I've seen these types of things before where people say, "It used to work..." and it turns out there's just a clog further down the line than they ran a snake. Sinks and dishwashers are notorious for fat and food clogs in the line.

 

[Greenman]

Normally, the sink trap empties into the wall and is introduced to a tee that vents to the roof (as stated before in this thread). That vent allows air to exit because it would have to gurgle through the trap otherwise to vent and allow the pipes to drain. If your sink is within 6' of the outside pipes, you could potentially add a vent there and it should still work, but it can't be too far below the sink or it would create the air lock you were describing if enough water got between the vent and the trap (which is why the vent should always be above the trap and no less than 6' away).

Did the pipes ever drain efficiently? I've seen these types of things before where people say, "It used to work..." and it turns out there's just a clog further down the line than they ran a snake. Sinks and dishwashers are notorious for fat and food clogs in the line.

Vent's prevent the trap from being siphoned dry and allowing sewer gas into the house. Based on those pictures, it appears the the sink isn't vented at all. It also looks like the dishwasher dumps directly into the drain. Hopefully there is a check valve in that line somewhere. I have no idea what that fitting is that the pipe is tied into, but I'd be inclined to look inside it. There also appears to be five vent 90's between the sink and the sewer main. That may be acceptable wherever the OP is located, it would never fly around here. I don't how you would ever get a snake through that mess.
My advice would be to rip it all out and replace it with the correct bends and a lot less of them, and install a proper vent.

It just occurred to me that the pipe the sink drain is tied into looks a lot more like a drainage system than a sanitary sewer.

 

[paperfist]

Those are PVC fittings like I've never seen before...

What is that threaded 'cap' on the bottom of the 2 sink tie ins? It almost looks like an upside down air arrestor.

Where's the P traps?

Is that the vent on the outside of the house?

 

[Greenman]

Those are PVC fittings like I've never seen before...

What is that threaded 'cap' on the bottom of the 2 sink tie ins? It almost looks like an upside down air arrestor.

Where's the P traps?

Is that the vent on the outside of the house?

I'm assuming the thing at the sink connections is some sort of trap, though that could be wishful thinking. I'm also guessing that the OP isn't in the US, and that the sink he's having trouble with was installed as part of a half assed remodel.

 

[Scarpozzi]

I'm assuming the thing at the sink connections is some sort of trap, though that could be wishful thinking. I'm also guessing that the OP isn't in the US, and that the sink he's having trouble with was installed as part of a half assed remodel.

That's what I was thinking. It looks like some kind of trap/cleanout....maybe to help catch grease clogs? It appears there's a rubber o-ring on top of the threaded fitting.

As stated, if there's no venting, that is likely what's causing the drain to be slow. It may have worked before, but if there's any clog or backup downstream, it could quickly cause the drain to slow even more.

 

[paperfist]

I'm assuming the thing at the sink connections is some sort of trap, though that could be wishful thinking. I'm also guessing that the OP isn't in the US, and that the sink he's having trouble with was installed as part of a half assed remodel.

I was thinking the same thing, different country. The flow doesn't even make sense the way it's laid out.

That's what I was thinking. It looks like some kind of trap/cleanout....maybe to help catch grease clogs? It appears there's a rubber o-ring on top of the threaded fitting.

As stated, if there's no venting, that is likely what's causing the drain to be slow. It may have worked before, but if there's any clog or backup downstream, it could quickly cause the drain to slow even more.

That's not a cleanout I'd ever want to work on
On the outside of the house looks like the closest to a vent in that whole setup, but it's too low.

What looks the strangest is that main pipe with the 'grease' trap looks like one piece.

 

[Scarpozzi]

That's not a cleanout I'd ever want to work on

I always put a bucket under those kinds of things...start to unscrew it and end up dropping it in the bucket and have to fish it out.

I do the same crap when I change the oil on my trucks. Doesn't matter how clean I'm trying to be, I always end up putting my hand in a bucket of warm oil.

 

[paperfist]

I always put a bucket under those kinds of things...start to unscrew it and end up dropping it in the bucket and have to fish it out.

I do the same crap when I change the oil on my trucks. Doesn't matter how clean I'm trying to be, I always end up putting my hand in a bucket of warm oil.

lol

When I do that the contain I use never holds what comes out of the pipes.