Dishwasher drain advice

[jjknob]

I am a recent new homeowner and am seeking some advice about how my dishwasher drain was plumbed. I've gotten nowhere with the builder as they're saying it's up to code and that's how they always do them. My issue is that my dishwasher runs very quiet until it begins to drain. At that point, it seems that the method used to plumb the drain allows you to seem like you're inside the dishwasher itself when it begins that part of the cycle. It's so loud and embarrassing if someone is over at the house! Never in my life have I heard a dishwasher drain this loudly. Yes, I understand you'll hear it to some degree, but this is just not right in my opinion.

I took a couple of pictures of how it was plumbed and it uses a "high loop" method with a separate p-trap and standpipe(which is apparently code in my county). Both the top of the standpipe and a Y angle fitting at the top are wide open(no air gap fitting) to the air and the dishwasher drain hose has a PVC elbow attached to it that just runs right into the open top of the standpipe. Can this possibly be right? Everything else(including in the dishwasher installation manual) shows that when using a high loop, you attach the drain hose to a tailpiece or into the disposer. My installation has neither method as you can see in the pictures. The one picture shows the separate P-trap and standpipe with the hose running up the side and you can start to see the open Y fitting toward the top of the standpipe. The other picture shows the top of the standpipe with the pvc elbow extension from the drain hose that just sits in the open standpipe, as well as the Y fitting.

Here's the addendum my county has adopted in addition to the 2012 IPC:
802.1.6 Domestic dishwashing machines Addition to the last sentence and separately trapped with the air gap located on the stand pipe.

Any advice in support or against this method would be greatly appreciated as it's driving us nuts and we feel like our hands are tied with the builder, but would love to have something a little quieter.

 

[Reach4]

Both the top of the standpipe and a Y angle fitting at the top are wide open(no air gap fitting) to the air and the dishwasher drain hose has a PVC elbow attached to it that just runs right into the open top of the standpipe. Can this possibly be right?

Maybe so. If the standpipe clogs, the water can run out, so the dishwasher could not suck sewage. Would a manufactured airgap fitting there make you feel better for some reason? I am not a plumber.

 

[Sponsor]

 

[jjknob]

Maybe so. If the standpipe clogs, the water can run out, so the dishwasher could not suck sewage. Would a manufactured airgap fitting there make you feel better for some reason? I am not a plumber.

do air gap fittings do anything to muffle the noise? If so, I'd feel much better!

 

[Reach4]

do air gap fittings do anything to muffle the noise? If so, I'd feel much better!

I would not think so, but I don't know.

If you grab that ABS while the noise is being produce does that cut down the noise? How about if you grab the nearby sink? The reason I ask is that if the noise is enhanced by a resonance, grabbing could help for identifying that. There are noise deadening materials, but I am not familiar with using those. I would think some sound absorbing material, could help with the sound.

 

[jjknob]

I would not think so, but I don't know.

If you grab that ABS while the noise is being produce does that cut down the noise? How about if you grab the nearby sink? The reason I ask is that if the noise is enhanced by a resonance, grabbing could help for identifying that. There are noise deadening materials, but I am not familiar with using those. I would think some sound absorbing material, could help with the sound.

I'll try it out, however I think I recall having my hand on the standpipe tonight and didn't notice any less noise. The noise is essential like someone slurping up the end of a soda that's gone times 50. The wide open y fitting and open top standpipe seems to enhance and echo the noise like crazy.

 

[Terry]

do air gap fittings do anything to muffle the noise? If so, I'd feel much better!

If the dishwasher is draining well, you will hear it. I've had that complaint before when I cleared a drain.

There are several ways we do this in Washington.
The most common in all codes is an air-gap on the counter. This can drain to a disposer, a tee fitting on a sink drain, or to a standpipe.
In the Seattle area, we have a standpipe with a "Johnson Tee". It also acts as an air-gap fitting.
If that isn't possible, then routing the drain line high before connecting is done. Some places don't use an air gap.
I'm not really liking an open standpipe like what you have. They don't do that here.

 

[jjknob]

If the dishwasher is draining well, you will hear it. I've had that complaint before when I cleared a drain.

There are several ways we do this in Washington.
The most common in all codes is an air-gap on the counter. This can drain to a disposer, a tee fitting on a sink drain, or to a standpipe.
In the Seattle area, we have a standpipe with a "Johnson Tee". It also acts as an air-gap fitting.
If that isn't possible, then routing the drain line high before connecting is done. Some places don't use an air gap.
I'm not really liking an open standpipe like what you have. They don't do that here.

I had read about the johnson tee and that sounded like a good much less noisy solution. There is direct access to the exterior wall of the house through the back of the cabinet, but I've been unsuccessful getting the builder to do anything to fix this for me. Thanks for weighing in!

 

[Reach4]

You might experiment by laying a big styrofoam cup or piece of carpet over the top.

 

[jjknob]

You might experiment by laying a big styrofoam cup or piece of carpet over the top.

good point, it's worth a shot! thanks

 

[Reach4]

If that helps, you might look into cutting up a small styrofoam ice bucket or bait bucket.

 

[Terry]

I had read about the johnson tee and that sounded like a good much less noisy solution.

Not really. I've had people complain about those too.

 

[jjknob]

Not really. I've had people complain about those too.

okay, bummer. All I know is that I've never heard a dishwasher drain this loudly before, but every other one I've ever had used a t-fitting I believe. Never had the open standpipe and air break y fitting they've done it with in my new one.