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pez372 03-14-2009 08:37 PM

installing a new dishwasher
I am installing a new dishwasher, and at the angle stop it is a 1/4 Inch outlet. I was thinking of putting a 1/4" x 3/8 coupling then run a 3/8 line to the dishwasher. Basically, I was wondering if the pressure would still be ok (~2 inch area near angle stop that is 1/4" line). From angle stop down through floor is 1/2 " CPVC. Under the house is 3/4 " line and 1" going to the pressure tank. Any input would be helpful. Thanks.:thumbup:

Mike Swearingen 03-15-2009 10:21 AM

I'm not a pro plumber, just an old DIYer.
Is that angle stop off of the hot or cold supply? If it's off of the cold side, it may be meant only for a refrigerator water/icemaker line.
A dw should be off of the hot side only. Since I believe that those dw supply lines are 3/8", I can't see why you can't do what you're thinking as long as it's off of the hot side. The pressure should be fine.
Good Luck!

Renovator,LLC 03-15-2009 05:13 PM

As the line will terminate in an open system (Dishwasher basin) pressure is not really the concern; but flow will be. It's possible that the smaller cross-sectional area of the 1/4" pipe will cause a 'choke flow', limiting the water flowrate, causing a longer time to fill the basin/tub. Other than that, it shouldn't be a problem. If the duration to fill is too long for you, you would have to shut the water off upstream of the stop valve and upgrade to a 3/8" valve.
And the dishwasher supply should be off the hot supply, unless your dishwasher has preheat capabilities, which would be required for every load, and will extend cycle time. Not really recommended.
Good luck.

Jacques 03-23-2009 09:52 AM

the minimum h/w supply line is 3/8 COPPER off 1/2 line. if you use flex line you have to go up a size. if you don't you'll have washabilty problems.
