Installing a dishwasher

[greencat]

I got my son a dishwasher for Christmas and have a question about the waste line. Normally they are installed next to a sink and are easy to install. Because of the layout of this old house it will need to be 8 feet from the sink.

I think I will need to run a new waste line and was wondering what size pipe to run. Can I avoid a new vent or if I need one I was thinking about using an air admittance valve.

Or could I get away with extending the discharge pipe that comes out of the dishwasher?

Thanks

[greencat]

I did a little research (should have done this before I posted this message) and decided to extend the discharge pipe under the floor and into the disposal instead of running a new waste line.

[kramer katt]

air gap

All diswasher installations should have an air gap before connection to GD (or to p trap if no disposal) Needed to prevent waste water back flow into DW
might be even more important given your distance from sink.
kk

[scorrpio]

Many new model dishwashers feature integral airgaps for both supply and waste. However, if your DW is on a separate waste line, it must have a P-trap and, unless within 3' from a stack, a vent. Ideal DW waste connection is to the DW outlet on the waste disposal unit/kitchen sink drain. Then, it uses sink's trap/vent.

Have to say, I'd go nuts if my DW was not right next to the sink. I would find it excruciatingly inconvenient.

[greencat]

Have to say, I'd go nuts if my DW was not right next to the sink. I would find it excruciatingly inconvenient.

I know what you mean but this about the only location without moving windows and or radiators. Thanks for your help.

[gsmittle]

I know what you mean but this about the only location without moving windows and or radiators. Thanks for your help.

Who needs windows?????

g.

[wbsettle]

Greencat, you might want to check the install manual for your particular model before extending too far. There's usually a spec limit on how much discharge hose the pump can handle. 8 ft of counter top distance could easily double when running the actual discharge line up/down/around stuff.

By the time, I finished installing a new DW earlier this year, I think I was right at or possibly exceeded the discharge limit by about a foot, but the distance is less than 6' as the crow flies and probably only 8'-9' linear running around the cabinet backs, including the lazy-Susan corner cabinet. The standard included discharge hose and extension kits availabel at Lowes aren't really designed to be cut to length. We also had to change to a smaller disposer to get the proper air gap height and avoid having to place a vent somewhere in the couter top itself.

-Brent