Kitchen Dual Sink Drains Slow not the knife valve

[davidaf]

Edited:

Either a clog or the vacuum isn't working. Water just takes forever to drain and yes the tank is empty. Sink plunger made no difference.

Wife claims that all of a sudden if both basins are full of water the kitchen sink now drains really slow and that it didn't before. I'm not gong to argue with her since I may end up on permanent dishes duty. Is there a vacuum breaker (2013 3400) or a vent to the roof for the galley sink? BTW doesn't matter if knife is open or closed same issue I was told.

Thanks.
dave.

[Overlord]

Clogged P-trap? Does she still have the wedding ring on her finger after doing the dishes?!

[davidaf]

Don't think it would be p-trap as they both drain well when the other side is empty. As much as she would like it, that rock isn't big enough to clog the trap.

quote:Originally posted by Overlord

Clogged P-trap? Does she still have the wedding ring on her finger after doing the dishes?!

[Irlpguy]

Look up on your roof, if you have a vent between the kitchen slide and the desk slide that is the one for the kitchen sink. Mine also had an auto air admittance valve in line with the roof vent. We were getting an odor from that valve so I capped it and with the roof vent we have no issues with the water draining from either sink or both sinks.
It seems not all units are plumbed the same, if yours does not have a roof vent that is properly hooked up, then I would suspect the Auto valve is sticking closed. Your problem sounds very much like a vent problem.
Mine is a 2012 - 3402RL but should have similar plumbing to yours.

[jcurtis934]

Does sound like a vent issue, unless you haven't dumped the galley grey tank recently... John

[davidaf]

galley grey tank is empty. Best I can guess is if there is some type of air check valve thing it's not easily accessible putting it near the water heater behind the wood panel. I check the p-traps and they were clean. Of course made a gigantic mess when i missed an o-ring during the leak test. Will have to do some more investigating.

[davidaf]

Tada, we have drainage. I found the vacuum thing, took that out and made sure it worked then ran a hanger down the line and poked it around. One of those procedures fixed the issue. I'm still going to run some enzyme cleaner down the pipes as my camera showed some muck down there.

[DQDick]

That little black can like devise under the sink substitutes for a roof vent and is notorious for sticking. They are used in home and business remodels also where it's not convenient to vent to the roof so new ones are available at most hardwares and box stores. A lot of the time just cleaning around the little plunger will solve the problem, but sometimes it's the spring getting old etc. and has to be replaced.

[davidaf]

What's interesting is I have the little can vent and I have a vent pipe going up to the roof. I didn't bother to climb up and make sure it goes all the way to the roof but it goes up to somewhere.

[DQDick]

That is strange. This makes no sense, but sometimes Keystone construction is like that, could the vent pipe be for the galley tank and the can for the sink?

[Irlpguy]

If the 3400 is plumbed in the same way that my 3402 is then the kitchen sinks are teed into the vent pipe from the holding tank, the pipe comes up behind the built in vacuum if you have one and then up behind the cupboard next to the desk slide to the roof. Also teed into the same plumbing was the air admittance valve (Black. Why they used both here is a mystery but they certainly did in my 2012.

In this picture you can see the hot and cold water lines that go to the sink and in the back right mostly hidden by the built in vacuum is the vent pipe from the tank, not in the picture is the tees from the sink and to the air admittance valve. I would guess you have both as do I.

[davidaf]

Irlpguy I have exactly as you do. Why both is certainly strange.