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edee_em

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Today, first time in 3 years of operation, our Bosch dishwasher threw an E15 error code. After reading up a bit on it, I tipped the machine to drain the water out of the pan and things seemed good.
Tonight, when I got home, the error code returned so I know what I'll be doing tomorrow.

I did notice a lot of crud in the abs drain pipe where the dishwasher hose connects to the abs piping under the sink (I have a separate branch running from top of cabinet down to arm joining the two sinks before the p-trap [see second pic])and that got me thinking about whether the way the installer configured the drain hose is okay.

The dishwasher is to the left of the open cabinet (in the first pic), in a peninsula and facing into the kitchen. The sink is directly behind the open cabinet back. . The second pic shows the plumbing under the sinks.
This cabinet faces into the eating area.

The configuration strikes me as "bad" as there is a definite "S" shape to it and there are two high loops (one where drain hose is connected to cabinet top in first pic and second where drain hose connects to drain pipe leading to trap). I'm thinking the two loops are causing some drain issues that may have stressed something and caused the E15 error. Thoughts? Thanks


20200122_145140[824].jpg20200122_192237[859].jpg
 
I doubt that backpressure from loops are the issue with the fault code.

Have a licensed plumber help address the situation if you are able to.
What you appear to have plumbing-wise, are a DW drain connected directly to drainage plumbing. Here in California and all places that the Uniform Plumbing Code is utilized, that type of connection is not allowed because a sink back-up can contaminate the DW hose and an imperfect closing solenoid on the DW can allow for cross contamination. This is what a Dishwasher Air Gap is for.
 
I should mention I'm in Ontario, Canada where air gaps are not required. The installation manual says that an air gap or high loop installation is acceptable, dependent on local codes. The local installer didn't install an air gap. I don't want to assume but I have to trust the pros, right?

I've also seen dishwasher adapter fittings that get glued into a wye fitting like I have. Again, the installer didn't do that but rather ran the abs up and then glued in an adapter that the drain hose is attached to.

breplum, is it that wye fitting that you're concerned with? For fun, can you give me a scenario where waste water would be making it's way up the abs, at that slope, to get into the dishwasher drain hose? I know that air gaps would stop a lot of that but isn't it roughly the same as a high loop? Or is it that the air gap allows the water to escape the drainage pipes so it doesn't make it's way to the dishwasher? Asking for a friend … :rolleyes:
 
The top rim of the sinks is a few inches higher than the top of the drain hose high loop.

So if the sinks were full to the rim, water level would be above the high loop, and would try to drain into the dishwasher.
If the sink drain line was not draining, or was backing up into the sinks.

Normally the dishwasher drain valve would shut to prevent back flow, but that can fail.
 
Thanks Jeff.
It is clear that we north Americans suffer from too-clean enviornments as we grow up. It is well documented that exposure to dirt, peanuts and cow's milk during early infancy, can effect resistance to many allergies, including asthma and resistance to dirty drinking water.
Nevertheless, most uniform code bodies utilize the "air gap" which completely separates any potential contamination from reaching any vector which could cross contaminate.
Details of what illness can lurk in the drain pipes:
  • Campylobacteriosis: Symptoms of this disease include fever, bloody diarrhea, abdominal pain, cramping, nausea, and vomiting.
  • Cryptosporidiosis: This waterborne disease causes a slight fever, diarrhea, loose or watery stools, upset stomach, and stomach cramps.
  • Diarrheagenic E. coli: Drinking fecal-contaminated water can expose you to E. coli, resulting in fever, watery or bloody diarrhea, abdominal cramps, nausea, and vomiting.
  • Gastroenteritis: Also known as the stomach flu, this infection causes fever, watery diarrhea, headaches, abdominal cramps, and vomiting.
  • Giardiasis: The Giardia parasite spreads this disease, causing diarrhea, loose or watery stools, upset stomach, and stomach cramps.
  • Hepatitis A: This viral liver disease is contracted from ingesting infected fecal matter. Symptoms include fever, fatigue, jaundice, abdominal pain, loss of appetite, nausea, and diarrhea.
  • Salmonellosis: Caused by exposure to Salmonella, this disease can cause fever, diarrhea, and abdominal cramps.
  • Dysentery: Ingesting contaminated fecal water can cause this disease, symptoms of which include fever, bloody diarrhea, and stomach cramps.
  • Typhoid fever: A bacterial disease spread through contaminated food and water, this disease causes high fever, weakness, cough, headaches, stomach pains, and loss of appetite. Some people also experience a rash.
 
playing devils advocate

i understand the air gap stops cross transmission of disease
i also understand that the diseases listed live and breed in a sewer line.
if you read the installation instructions of a dishwasher it says the hose must exit the dishwasher at the bottom,
Loop up to the top of the unit, then down to the bottom of the cabinet. see image

the local codes require the hose to loop up, and connect to an air gap fitting.
isnt the same dirty water that is in the sewer trapped in the hose?
between the air break and the unit? see image


dw1.png
dw2.png
 
Sounds like an air gap device is a US thing and that's pushing it as many states or localities don't have codes for air gaps (in my limited research). Read some disgruntled types in MN are looking for a do-over as they just introduced air gap code there recently. As mentioned, not mandated up here. I get the logic but someone mentioned some manufacturers are putting air gap devices right on the dishwashers. So, who knows where all this will end. Funny how we're still here 62 years later without an air gap on our dishwashers.
 
frodo, you are right that dirty wash water will be trapped in the line, by one or more high loops.

But unless you are putting turds and sewer sludge into your dishwasher, the levels and types of bacteria and contaminants are not nearly as serious.

Not as serious as a house drain line, with poop, backing up into the sink drain.
 
frodo, you are right that dirty wash water will be trapped in the line, by one or more high loops.

But unless you are putting turds and sewer sludge into your dishwasher, the levels and types of bacteria and contaminants are not nearly as serious.

Not as serious as a house drain line, with poop, backing up into the sink drain.


good answer Jeff
we run across situations that we see daily where we question the code
this is one of those situations.
will the loop to the garbage disposal work where you are utilising the disposal as an air break?
answer is yes
Will the situation that you layed out where the sink completely fills and runs over
causing waste to enter the loop?
answer is..yes 1 in a million, but the answer is yes
the plumbing code protects the public from that 1 in a million.
sometimes we do not agree,
take for instance the vacuum breaker on a hose bib

IF the city was working on the water main
IF that job was being done down hill from your elevation
IF you stuck the hose in a bucket of poo poo
AT the exact moment the city cut the line and the water caused a vacuum
then that little Vb would save your life
will any of the above happen? 1 in a million, but it could
 
God, those vacuum breakers on a hose bib are often annoying.

I often use a hose to water plants, and I like to keep the pressure down by only opening the hose faucet a little bit.
So I don’t blast the plants too hard.

But usually, that vacuum breaker will piss and waste water unless the faucet is pretty well fully opened.
 
If only we could figure out if any codes would be around if the word "if" didn't exist? Now where's that smartass emoji????
 
at one point in history we did not have plumbing codes
we had plague ,leoporsie, typhoid. etc etc instead
Actually Frodo I would suggest we didn't have plumbing, let alone codes. Watched a pretty interesting documentary series that looked at the history of Britain, room by room. One of those rooms was the bathroom and we can see that indoor plumbing and sanitation is a pretty recent undertaking (relative to the times).

In my previous career to my current gig as "diy know-nothing" I taught economics and at some point in the course I would ask every student in every class if they thought a doctor was more important than a plumber. Every student raised their hands for doctor, of course. I would ask why, and they would say they help people, cure diseases, etc. Some would be honest and say money. After a lot of discussion back and forth I point out that it is easier to cure a disease that a person doesn't have. They would have that same bewildered look you probably have on your face right now.

I essentially took them through disease over time and where some of those nasties are most prevalent today (think third world where proper sanitation doesn't exist). Diarrhoeal disease is still one of the leading causes of death worldwide and it is the number one killer of children. I then tell them to go home and tell their parents that they are changing their career path to plumbing. I don't think I changed any one kid to become a plumber but I do know that most of them picked up a new respect for them.
 
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@Jeff Handy your upset--rightfully so--with vacuum breakers on a hose bibb can be solved by using a "frost-proof" hose bibb with integral vacuum breaker. I've never known these to backsplash water into your face like the screw-on types. Yes, they are most costly than a boiler drain/hose bibb, but they work well and prevent such things. The only thing you have to be very careful with is to REMOVE the hose when cold weather approaches...if the hose is attached and you have a freeze, the vacuum breaker is toast and you have to replace the entire unit. Want to know why I know that? :)

The talk of disease and codes etc. is all very enlightening, and the reference to Britain interesting. Most of UK still doesn't have mixing faucets, you have "third degree burn scalding hot" on the left tap, and "ice cold like the beer should be" on the right. They actually think this is good, and expect you--even in a public restroom, to wash your hands in a sink full of warm water you make by mixing the hot and cold. Ah, no thank you. But that only begins the plumbing weirdness across the pond. Ever hear of "electric showers"? Neither did I until my B&B in Edinburgh had one. Look them up. And to think my mother always told me not to touch a switch with wet hands!

I am all for safe water, and codes and tools and parts to ensure we all don't get sick. But as a former car wash owner, I was irritated that my 2" RPZ (that fed the 100,000 gallons of water I used PER MONTH) needed annual checking at a cost of $125. No, the county didn't do it, they listed just 25 county plumbers "licensed" to hook up a Watts TK9A and read a few gauges. Oh, and as long as they are there they'll have to test the irrigation vacuum breaker. They never failed, even though they were over 20 years old. Shouldn't a test procedure be related to MTBF or something similar? I considered that $250 annually a stupid, unnecessary tax.

And to reiterate what @frodo said, at my car wash (like others), I'd have to have had a cascading failure of a number of check valves, vacuum breakers, and even air gaps, all at the same time, combined with BOTH sections of the dual RPZ failing in a way they were not designed to fail (when an RPZ fails, they dump to drain, they don't allow backflow!), all at the same time as a massive power failure in the town combined with a vacuum on the water main...and IF that impossible scenario were to ever exist, what would have happened? Dilute detergent (yes, soap) might have entered the city water system. This is what I thought every year as I wrote out that check to the guy testing the RPZ...
 
Just a tidbit of info regarding RPZ's.
Under the right conditions they CAN allow backflow into a potable water line.

An air gap is considered the maximum protection available against back pressure backflow or back siphonage, but is not always practical and can easily be bypassed.
airgp1lg.jpg
 

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