Dishwasher Discharge Connection

**Bruce Breedlove** · 09-29-2007, 04:18 PM

This is in a mobile home. (It was described to me as a "modular home" but it turned out to be a double-wide.)

The dishwasher discharge is connected directly to the tailpiece of the kitchen sink. The connection point is directly opposite the drain from the second sink. I can envision the force of the water discharging from the dishwasher pushing water up into the second sink and up into the primary sink if the second sink is draining when the dishwasher discharges. I can also envision water backflowing from the sink drain into the dishwasher if the sink drain piping becomes clogged.

The dishwasher does not have an air gap or an air break nor does it have a high loop. Around here the AHJ discourages high loops but the AHJ does not inspect MHs (unless modifications are made requiring a permit).

This inspection was a while back but I am curious how, or if, others would report this connection.

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**Rick Cantrell** · 09-29-2007, 04:44 PM

Bruce
I have not seen a tailpeice like that one.
But on the ones I have seen, there is a baffel that directs the flow of water from the second sink.

Of course we know that if a company made it and another company sold it, well ,,, then, it must be OK to use.

**Eric Barker** · 10-01-2007, 10:41 AM

Bruce,

I would not go along with that configuration.

I betcha there's a big difference here. You're signing your name on a report, the AHJ is not. Funny how someone will twist and turn when you ask for their opinion to be put onto a signed document.

William Mize · 10-01-2007, 01:12 PM

any idea why he discourages high loops, seems to me they are better than nothing and who wants another hole cut in their cabinet top for an air gap

Willie

**Rick Hurst** · 10-01-2007, 02:25 PM

Bruce,

At least the DW drain hose in your picture has a tight connection.

**Robert Dalga** · 10-02-2007, 06:04 AM

I would write it up as an incorrect installation and recommend dishwasher drain line be looped up high (simple, but effective fix). Minor problem only.

**Bruce Breedlove** · 10-02-2007, 02:20 PM

I don't know why the local AHJ don't like high loops. I'll have to ask next time I am over there.

The pic below is the way we like to see dishwashers drained around here. We have an air gap and the notch cut into the top of the drain pipe prevents a cross connection. And the dishwasher discharge is secured to the drain pipe.

Now I'll wait for Jerry to point out what's wrong with this arrangement.

**Jerry Peck** · 10-02-2007, 03:41 PM

Originally Posted by Bruce Breedlove

Now I'll wait for Jerry to point out what's wrong with this arrangement.

Bruce,

You mean besides the fact that the air gap *is below* the flood level rim of the sink, which means that if the sink drain backs up you will have crap (literally) spilling into and out of the cabinet.

You mean besides the steel (stainless steel) strap on copper.

You mean besides that is an 'air break' and not an 'air gap'.

You mean besides ...

**Bruce Breedlove** · 10-02-2007, 08:30 PM

Doesn't the notch change it from an air break to an air gap?

**Jerry Peck** · 10-03-2007, 07:37 PM

Originally Posted by Bruce Breedlove

Doesn't the notch change it from an air break to an air gap?

Not technically as the air gap is between the bottom of the pipe draining into the receptor and the top of the receptor, in this, the PVC pipe.

The notch helps, but it's not a true air gap. Imagine that water being pumped out of the dishwasher drain hose (the copper pipe) and splashing around inside the PVC as it is forced down, don't you think that some of that splashing water is also splashing back up and around the PVC - right where the copper pipe is?

Look closely at the residue on the 'outside' of that copper pipe.

**Eric Van De Ven** · 10-04-2007, 09:57 AM

Originally Posted by Bruce Breedlove

This is in a mobile home. (It was described to me as a "modular home" but it turned out to be a double-wide.)

The dishwasher discharge is connected directly to the tailpiece of the kitchen sink. The connection point is directly opposite the drain from the second sink. I can envision the force of the water discharging from the dishwasher pushing water up into the second sink and up into the primary sink if the second sink is draining when the dishwasher discharges. I can also envision water backflowing from the sink drain into the dishwasher if the sink drain piping becomes clogged.

The dishwasher does not have an air gap or an air break nor does it have a high loop. Around here the AHJ discourages high loops but the AHJ does not inspect MHs (unless modifications are made requiring a permit).

This inspection was a while back but I am curious how, or if, others would report this connection.

I wonder what code they are operating under.

Here it would be this:

409.3 Waste connection.
The waste connection of a dishwashing machine shall comply with Sections 802.1.6 and 802.1.7 as applicable.

802.1.6 Domestic dishwashing machines.
Domestic dishwashing machines shall discharge indirectly through an air gap or air break into a standpipe or waste receptor in accordance with Section 802.2 , or discharge into a wye-branch fitting on the tailpiece of the kitchen sink or the dishwasher connection of a food waste grinder. The waste line of a domestic dishwashing machine discharging into a kitchen sink tailpiece or food waste grinder shall connect to a deck-mounted air gap or the waste line shall rise and be securely fastenend to the underside of the sink rim or counter.

802.2 Installation.
All indirect waste piping shall discharge through an air gap or air break into a waste receptor or standpipe. Waste receptors and standpipes shall be trapped and vented and shall connect to the building drainage system. All indirect waste piping that exceeds 2 feet (610 mm) in developed length measured horizontally, or 4 feet (1219 mm) in total developed length, shall be trapped.

802.2.1 Air gap.
The air gap between the indirect waste pipe and the flood level rim of the waste receptor shall be a minimum of twice the effective opening of the indirect waste pipe.

802.2.2 Air break.
An air break shall be provided between the indirect waste pipe and the trap seal of the waste receptor or standpipe.

**Jerry Peck** · 10-04-2007, 12:37 PM

Originally Posted by Bruce Breedlove

This is in a mobile home.

Originally Posted by Eric Van De Ven

I wonder what code they are operating under.

None of those.

Mobile homes are manufactured under (mind going blank here ... ) HUD or some other regulations, not regular building codes.

**Billy Stephens** · 10-04-2007, 01:22 PM

Originally Posted by Jerry Peck

Mobile homes are manufactured under (mind going blank here ... ) HUD regulations, not regular building codes.

Mc Mansion on Wheels.

HUD- Manufactured Housing and Standards

**Eric Van De Ven** · 10-04-2007, 01:41 PM

Interesting enough, Maytag at least, doesn't mention anything about a high loop or air gap in their instructions.

http://www.maytag.com/assets/product/6918789B.PDF

Originally Posted by Jerry Peck

None of those.

Mobile homes are manufactured under (mind going blank here ... ) HUD or some other regulations, not regular building codes.

This: http://www.access.gpo.gov/nara/cfr/w...fr3280_06.html
Have fun reading that!

Maybe that is why there aren't many left down here, at least near me, after hurricane Wilma.

Hopefully, they will all be eliminated. They are called "mobile" for a reason. After a big storm...they are gone!

On a related note, I got a call from a Realtor who had a client that was going to buy a manufactured home here and move it to the west coast of Florida, until he found out, that unless it was built after 1994, they wouldn't allow it.