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Dishwasher waste - Need options for preventing blockage?

I have a dishwasher with a fairly standard waste pipe, the issue is that where it attaches to the S bend under the kitchen sink there is a "barb?" attachment (not sure if that's the right name for it). Anyway the problem is that the flow through the barb is the narrowest point and I very regularly get a blockage right in that place. It's not vey difficult to clear, but I was wondering if there is a better, less blockage prone option I could change to?

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MitchellMc

Welcome to the Bunnings Workshop community @Zadam. It's fantastic to have you join us, and many thanks for your question about attaching a dishwasher.

Can you check for me that the barb has been entirely drilled out? Have a look down the end of it to see if any of the plastic stop has been left. Perhaps someone hasn't drilled it out to full size.

Typically, the barb on the S bend should be more than adequate for the flow of water out of your dishwasher. What are you clearing that's causing the blockage?

Please let me know if you have any questions.

Mitchell

Zadam

Thank you Mitchell!

Yes I did check that, and it seems to have been drilled out to the full diameter of the inside of the barb.

The blockage is typically caused when some moderate sized fairly hard food debris goes through the dishwasher and I guess makes it past the filter. I assume it needs to be a fairly specific size as anything smaller would go straight through, and anything larger would probably not make it into the waste hose in the first place.

Zadam

Another possibility I just thought of is that it may be food debris from the sink that is causing the blockage, not from the dishwasher. I'm thinking along the lines of water with food debris going down the sink into the S bend, and some of it actually going slightly back up into the barb, and then getting stuck.

MitchellMc

I don't use my dishwasher, but every time I'm at someone's house that does, they tend to rinse plates off before going in the machine @Zadam. It's potentially due to the same reason. I understand that's a bit of double-handling and is one of the reasons why I don't use mine. I figure if I have to rinse them off, I might as well just wash them.

I am not aware of any fittings that would allow the full-sized pipe to flow unrestricted into the trap. You could potentially cobble something together, but then, if the hose slips inside a fitting, you'll need to find a way to hold it in there so it doesn't blow out. That's the reason for the barb on the trap.

Mitchell

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