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Dishwasher drain question - heat

Skyman

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Hi, all.

I'm correcting a poor installation of a dishwasher to a disposal. The hose is a bit short for the application, which is trying its best to put a kink into the adapter at the end of the hose. Without thinking it through as much as I should have, I bought a few feet of PVC hose and a PVC right-angle barb coupler with which to extend the existing hose. It belatedly dawned on me that the water coming out of the DW is going to be hot. I don't know how hot, but I'm guessing it might be near, at, or beyond the rated temperature of these PVC components, in which case it's time for a new plan. Should I move to Plan B (which I'm thinking would be brass hose barb coupler(s) and automotive heater hose?

Problem:

1763322760377.jpeg


Plan A:

1763322793766.jpeg


TIA for any advice.
 
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tarmy

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My plan A would be to relocate the hose to the bottom of the DW bay. That way there is suffclient hose to fix that problem. Requires a new hole in the cabinets.
 

BurtEggley

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I'd warm the existing hose along its length with a hair dryer and stretch it a little to see if that helps get you a couple extra inches of hose length, then watch it to be sure it did not return over time to a kink. Or get a longer hose. They make hose extensions and couplings but they are likely to cost more than a whole new hose.
 
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Skyman

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I contemplated yanking the DW out of its hole for a new, longer hose but it’s a lot quicker and easier to just add a little to the hose under the sink.

My aging memory is saying something about the hose needs to be run up to just below the countertop. If that’s correct, rerouting it lower to shorten its route is not going to be up to code.
 

Fav Onefour

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Most of the normal consumer dishwashers need a high loop in the drain line. Leave that loop where it's currently located.

I recently helped some friends on a remodel of their original 1970 ish kitchen. The drain hose on that dishwasher looked like it was heater hose used in vehicles.
Honestly, I was impressed that the dishwasher made it that long. The hose was a surprise.
I've had a few regular dishwasher hoses crack and leak in much less time.
Not that I'm recommending heater hose, but dishwashers don't need a special kind of hose. On the other side of the discussion, I've seen ready made dishwasher hose extensions sitting on the shelf in the ol big box stores. That would be the easiest route by far.

I'm trying to figure out the drain configuration. Is the disposal going into it's own separate trap while another sink basin goes into it's own trap? It just looks odd and I can't see the rest so I'm guessing. I'm asking because I'm wondering if you could reconfigure the drain assembly. I know it's more work, but your next dishwasher will likely have a similar issue with the drain hose.

BTW, one of your disposal retainer screws is completely backed out. Tighten that ****** before you're repairing water damage.
 

mike93lx

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I contemplated yanking the DW out of its hole for a new, longer hose but it’s a lot quicker and easier to just add a little to the hose under the sink.

My aging memory is saying something about the hose needs to be run up to just below the countertop. If that’s correct, rerouting it lower to shorten its route is not going to be up to code.
You need to raise it up high then come back down to create a trap, otherwise your dishwasher will smell terrible.
 

jblnut

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Ditch the garbage disposal and get a couple hogs.

Replumb the dishwasher drain through the hole where the sprayer would go and direct it into the sink so it’s plumbed like it was at my Grandparents place. Never understood that one but they also had a deep utility room slop sink in the kitchen so who knows lol

We have a longer than normal hose on our dishwasher. Wasn’t difficult to put on and it sure isn’t difficult to pull that dishwasher out. Gonna spend less time and hassle doing that than cobbling something together.
 

OccupantRJ

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Can you detach the hose, reroute it higher and closer to the sink bottom, then attach it to something to keep the hose from sagging? Several of the adhesive zip tie mounts may work, or you may can attach support(s) to the cabinet.
 

Bunsen Honeydew

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Rerouting the drain hose in front of the supply lines may give you some extra length. I bet the supply lines are putting tension on the drain, pulling it back, thus encouraging the bend.
The hot water sink supply line has trapped the drain between it and the back of the cabinet.
 
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mm08822

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Where is this drain coming from? I'm in the reconfigure the drain and rotate the disposal to face the dishwasher camp, if possible.

1763386944678.png
Yes, this drain line is confusing. Can't tell if it is in use, abandoned or....? If not needed, replace it simplify the plumbing.

Also the disposal to sink interface is leaking so reworking that connection now with the dw hose reconnection on the otherside make sense.

Also pointed out that one set screw is doing nothing.
 
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Skyman

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Thanks all for the replies and advice. I had not noticed the loose screw, so thanks especially for pointing that out. I will address that promptly.

It's apparent to me that the disposal was added by the previous owners of this house. The stub that was asked about (identified by racecougar's red arrow) is capped, having been the original waste line prior to the poor installation of the disposal.

1763393797176.jpeg
 

dave*99

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I wonder if that used to be a dual basin sink.
My old house had a wye like that. No disposal, but one branch of the wye went to dual basins and the other to a standpipe under the sink for the DW. At one point they were not allowed to use a tailpiece with a DW port. No idea why - it was 40 years ago.
 
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Skyman

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It's impossible for me to say with certainty whether there was originally a dual basin sink here, but my supposition is that the disposal was added after the house was built, since the place is not connected to public sewer. I would not have added a disposal, and don't use it other than to flip it on occasionally to keep it from seizing due to non-use. I added a strainer to the sink drain, and everything it captures goes into the trash. If the disposer ever creates a bigger problem than what I'm dealing with now, I'll dispose (intended) of it. For now, that looks like unnecessary mission creep, and I have plenty of other priorities.
 

Meursault74

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I used a brass 90 degree fitting to address a kink in my disposal line.

It was the sharkbite brand "made for pex". It fit into the PVC line that was actual DW line and I secured it with hose clamps. I installed it between the air gap and the disposal. This was easier than getting a longer line. Locally the line was either too short or way too long (meaning I'd have to pay for extra I didn't need). Seems to be holding fine.

1763616149767.png
 

wolfhawk73

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Definitely keep that high loop. You don't want sink water to back-flow into the dishwasher. Most dishwashers have check valves just downstream of their drain pumps, but those valves aren't always strong enough to stop a sink full of water being drained all at once.

Based on what I see, I'd recommend buying an extension drain hose from the manufacturer. Just about every company offers it as an accessory for a situation like yours. Putting in an elbow might cause a clogging issue down the line.

When dishwashers run a Sanitize option, the water will get up to 72 °C/162 °F for 10 minutes (an NSF requirement to be able to claim the load is sanitized), so it gets pretty toasty. Just make sure that any drain hose other than a manufacturer's extension hose is rated for it. I wouldn't use the one in your picture just because of its tendency to kink.

Personally, though, I'd get rid of the disposal. The connection in my disposal for the dishwasher drain rusted and swelled a few years ago, causing a slow leak that was luckily caught by a pan full of cleaners. I just hit up the hardware store nearby for about $25 in parts and got rid of the disposal. It was convenient to use, but so is the trash can. I don't have to run an ice/bleach slushy every so often anymore to get rid of the funk. My sewer system is happier, too.
 
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Skyman

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Thanks to all for the feedback. It's all much appreciated.

I do intend to eventually remove the disposal, but that's going to be a mission for another day, and not until sometime next year. For now, that's just not making it near the top of the lengthy list of priorities in my life. We're on septic here, so the thing really should have never been installed, but that was done before we arrived here. I probably only run the DW once a month or thereabouts, as I prefer to just hand-wash dishes. The DW is exercised only when there's a larger gathering here for meals. So, for now, a temporary alteration to eliminate the kink that's developing at the connection to the disposal will suffice.
 

whejdak

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I am surprised that no one has mentioned "The Air Gap"
Recently I had a plumber come in to clean out the drain. He mentioned that I had the dishwater hose connected directly to the garbage disposal and not to the "air gap". I didn't know what he was talking about. But in Wisconsin by code, the diswasher should be connected to the air gap device and then from the air gap device to the drain. Typically, you see the air gap device poping out of the sink and looks like some kind of air breathing device.
Seems like there isn't a gap like I mentioned in the conversation.
Look up Air Gap Kits on the internet to see what I am talking about.
If there isn't a hole in the sink already with the chrome looking thing sticking out, then forget my whole conversation.
 

dave*99

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I know what an air gap is. I have read about them. I have never seen one in New Jersey.

I’ve read a high loop is compliant in NJ as long as the DW drain is terminated more than 20” above the floor.
 
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Meursault74

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I am surprised that no one has mentioned "The Air Gap"
Recently I had a plumber come in to clean out the drain. He mentioned that I had the dishwater hose connected directly to the garbage disposal and not to the "air gap". I didn't know what he was talking about. But in Wisconsin by code, the diswasher should be connected to the air gap device and then from the air gap device to the drain. Typically, you see the air gap device poping out of the sink and looks like some kind of air breathing device.
Seems like there isn't a gap like I mentioned in the conversation.
Look up Air Gap Kits on the internet to see what I am talking about.
If there isn't a hole in the sink already with the chrome looking thing sticking out, then forget my whole conversation.
I had mentioned the air gap. I had used a brass 90 between the air gap and the disposal as the hose kinked a little just like the OP. Supposedly the high loop in the line should accomplish the same thing. When I changed the DW I put in new everything including the air gap. There's a hole in the sink for it and the plastic apparatus is low cost.

I haven't shopped for kitchen sinks in a long time. I wonder if they come with the hole for it and you either put a blank in there or a soap dispenser if you don't want an air gap. Maybe they only drill the hole if it ships to an area required by code. I think it's required by code in my area, but that didn't concern me. There was one there, so I just kept it the same. With the access to my under sink area being what it is, setting up a high loop would be more trouble than using the air gap.
 
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Skyman

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Adding an air gap in this kitchen would require boring a hole through a slab of granite and the flange of the under mount sink. That won’t be happening.
 
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