I've installed a dishwasher in a new cabinet and countertop section in my
kitchen and need help with addressing proper drainage. It's not near the
sink. I have the drain loop running up and around the washer, but the
existing drop is just above the floor and runs straight down into the
basement. This creates a siphoning after the initial wash, so when it
refills for the rinse, the water keeps siphoning out. Obviously, I can't
install the typical air gap that's used on sinks because I can't risk any
backup flooding under the cabinet section. I've heard something about using
a "Y" connector type air gap that connects near the floor but runs up the
wall and is capped off with, I'm guessing, a filter that only passes air (or
maybe it's some kind of one-way valve or ball frit?). Is anyone familiar
with setting this up or does anyone have any advice on how to make my
current setup work correctly? I've seen dishwashers installed in kitchen
islands with no sink, so there must be a common way of connecting this
properly.

Thanks.

First, the device you are thinking of, is an air admittance valve.
They are one way air valves, that let air in, but not out . They are
used in areas where a conventional through the roof vent is not
possible, like your island kitchen example. However, they function
along with a regular trap and as far as I know, come in sizes made to
fit that type of arrangement, ie 1 1/4 up. So, it not clear how you
can easily work one into your arrangement.

Second, are you sure that is your problem? What I'm having difficulty
with is how a syphon could continue to operate. I would think that as
soon as the dishwasher is pumped out and there is no water left, the
syphon would break by drawing air into the line from the bottom of the
dishwasher. That should happen before it starts to fill again.

Milky-G wrote:

I've installed a dishwasher in a new cabinet and countertop section in my
kitchen and need help with addressing proper drainage. It's not near the
sink. I have the drain loop running up and around the washer, but the
existing drop is just above the floor and runs straight down into the
basement. This creates a siphoning after the initial wash, so when it
refills for the rinse, the water keeps siphoning out. Obviously, I can't
install the typical air gap that's used on sinks because I can't risk any
backup flooding under the cabinet section. I've heard something about using
a "Y" connector type air gap that connects near the floor but runs up the
wall and is capped off with, I'm guessing, a filter that only passes air (or
maybe it's some kind of one-way valve or ball frit?). Is anyone familiar
with setting this up or does anyone have any advice on how to make my
current setup work correctly? I've seen dishwashers installed in kitchen
islands with no sink, so there must be a common way of connecting this
properly.

Thanks.



You can use an auto-vent device:
http://www.plumbingsupply.com/autovent.html

But first.... Is there a P-trap in the basement where
you are connecting in to? If not, you have a bad situation.
Without a trap, there is always the possibility of sewer gas
exiting the dishwasher.

Even if the sink is a long distance away, I would route the
drain to the sink trap (inlet) or to the disposal (if present).

Jim

"Milky-G" wrote in message
...
: I've installed a dishwasher in a new cabinet and countertop
section in my
: kitchen and need help with addressing proper drainage. It's not
near the
: sink. I have the drain loop running up and around the washer,
but the
: existing drop is just above the floor and runs straight down
into the
: basement. This creates a siphoning after the initial wash, so
when it
: refills for the rinse, the water keeps siphoning out.
Obviously, I can't
: install the typical air gap that's used on sinks because I
can't risk any
: backup flooding under the cabinet section. I've heard something
about using
: a "Y" connector type air gap that connects near the floor but
runs up the
: wall and is capped off with, I'm guessing, a filter that only
passes air (or
: maybe it's some kind of one-way valve or ball frit?). Is anyone
familiar
: with setting this up or does anyone have any advice on how to
make my
: current setup work correctly? I've seen dishwashers installed
in kitchen
: islands with no sink, so there must be a common way of
connecting this
: properly.
:
: Thanks.

Actually, you should be able to handle that by tapping it into
the sink drain, at the P trap, and just be sure one part is hung
high enough to be higher than the entry point to the drain. You
don't HAVE to run it down thru the floor.
Probably a PITA, but run the hose thru the backs of the
cabinets, or even into a different P trap if there's one around
downstairs; all you need's a place to let some air in. The one
way air trap gizmos also work well, but I also discovered they
leak after awhile from the crud collection, so you want it where
you can get at it easy to check and/or change it out.
But, as you found out, you do need something to allow the
suction to break. Common problem lost of diy-ers run into the
first time. Including me g.

If this is a Fisher and Penkall drawer dishwasher, it requires special
drainage attention. The drainage pipe must be low and have no kinks and
only go up to reach the final drain exactly as shown in the installation
manual or you will have problems.


"Milky-G" wrote in message
...
I've installed a dishwasher in a new cabinet and countertop section in my
kitchen and need help with addressing proper drainage. It's not near the
sink. I have the drain loop running up and around the washer, but the
existing drop is just above the floor and runs straight down into the
basement. This creates a siphoning after the initial wash, so when it
refills for the rinse, the water keeps siphoning out. Obviously, I can't
install the typical air gap that's used on sinks because I can't risk any
backup flooding under the cabinet section. I've heard something about
using a "Y" connector type air gap that connects near the floor but runs
up the wall and is capped off with, I'm guessing, a filter that only
passes air (or maybe it's some kind of one-way valve or ball frit?). Is
anyone familiar with setting this up or does anyone have any advice on how
to make my current setup work correctly? I've seen dishwashers installed
in kitchen islands with no sink, so there must be a common way of
connecting this properly.

Thanks.