New F&P DishDrawer spray arm!

[DADoES]

F&P has done a redesign on the DishDrawer spray arm, probably as part of the KitchenAid offering. Leslie (Magic Clean) was so kind as to send one to me for a test run. Notice the change in hole / spray pattern.

The first load I ran included the usual mix of plastic storage bowls and lids. There generally is quite a bit of clattering and bumping noises as the bowls jiggle and bounce when the spray passes, and lids are dislodged from the original loading positions. I can't say for sure based on just the one load what is the overall effect of the new arm, but there were NO clattering noises with the redesigned arm and the lids were not blown about. Very interesting!

 

[gansky1]

Cool - was there a change in the overall noise level of the machine?

 

[westytoploader]

Interesting...I do remember some clattering in the old spray arm (above the quietness of the machine itself) on the "light" load. I wonder if the fact that more spray jets creates a "sprinkler" effect instead of "power-spraying" them.

Have you tried it yet with pots/pans?

 

[peterh770]

Is it an optical illusion from the pic, or is the spray arm longer?

More spray holes, if no increase pressure from the pump means that the pressure of the spray is weaker -- or quieter so they don't have to increase sound insulation.

 

[DADoES]

They're identical in size. One looks longer because of the angle at which the picture was taken.

Yes, I imagine the spray pressure is lessened, but cleaning on the initial load was perfectly fine. I'm anxious to see the results on a 'challenging' item. An 'original' arm is in the lower drawer, so those items can go down there if there's any negative impact on performance (which I doubt F&P would intend for that to be the case). Leslie said the general gist of the new arm design is for "improved performance" -- whatever exactly that means! Could be for improved spray coverage, although at lessened pressure, along with a slight reduction in operational noise.

 

[mrcleanjeans]

the HOLE truth

Why is there that extra big hole in both spray arms?

 

[DADoES]

I have no idea. If you notice on the better view of the 2nd arm, there's a little metal flapper inside that large spray hole. That's not a change, the 'old' arm has it as well.

 

[nmaineman36]

the large hole

That large hole on the arm has a metal flap on the inside and its moves on up to close the hole during wash. During drain it opens up to let the wash arm drain completely. There is also a jet under the spray arm that cleans off the filter. In the year that Scott has had the dishwasher the filter has never been dirty. The trap filter at the drain port does get pretty nasty but that is easy to clean. I just run it under a strong stream of water and clean the mesh.
As far as the water pressure for the new arm design, I would think that since the dishwasher has the Smart Drive it would sense the amount of water passing into and adjust accordingly. The dishwasher doesnt run at one speed like most machines...it will vary the pressure from load to load and to what cycle and to what you are washing in it.
Mike

 

[DADoES]

Mike,

So the hole with the flap is a sort of siphon-break for the wash arm? Interesting. Wonder why that's necessary since there are plenty other spray holes?

My original wash arms do not have a filter spray jet underneath. The new arm does.

According to the tech sheet, the motor runs between 2300 and 2800 RPM to recirculate for the various cycles (or maybe it's between 2500 and 2800, I don't recall exactly and I don't have the sheet handy at the moment). I don't recall specific mention that the speed varies to get a target spray pressure, although I suppose that's possible. It does use motor load feedback to determine proper fill level.

 

[kenmore1978]

extra holes in spray arm

So maybe the extra holes in the new arm increas the "needling" effect like the Frigidaire spin tubes?

Also didn't the later 4 arm KA wash arms have a hole underneath that sprayed the filter?

 

[lightedcontrols]

EXTRA HOLES

Am really glad that F&P did a redesign on the spray arm. These machines have a hard time even getting plates clean, much less anything else. I will be putting 3 of these new machines with the KitchenAid badge in my new home to use as bar dishwashers. Will be VERY interesting to see how they perform. I figure at the least they SHOULD be able to wash glasses! Mark

 

[DADoES]

Oatmeal

I ran another load a couple days ago (haven't unloaded it yet, sorry, I'm busy with two jobs and an elderly grandmother). One item was a 12-cup muffin pan, which I laid atop the rest of the load. It did clatter, so I paused the cycle and placed a Visions pot lid on top of it, LOL. Two other items were bowls from instant oatmeal that had been left for several days to get dried and crusty. Loaded them on the fold-down shelf at the left with the usual assortment of cups/glasses beneath, and other items around. Both bowls came out sparking clean. I dunno how they'd come out with the original arm, but there doesn't appear to be any cleaning impairment with the new arm.

 

[bwoods]

pressure of new wash arm

By lessing the diameter of the holes in the wash arm, the pressure of the water escaping from each arm is acutally greater, not lesser. If you remember from physics, Bernouli's equation states that for a given orifice, as the diameter gets smaller, the velocity of the fluid coming out gets greater. However, there is a smaller mass of water passing through the holes so dishes are not disloged and jostled about. That's why you didn't hear any movement in dishes in the F&P with the newly designed arm.

I've done experimental work on my own with dishwasher arms, just for fun. Small holes are good for loosening foods but larger holes give more of a flood of water which is good for washing loosened soil away.

To visualize this, think of your garden hose. With no nozzle on it, there is a large mass of water but not a lot of pressure. Put your thumb over the end of the hose and you effectively cut down the size of the opening, water velocity increase and the water shoots out further with more force.

When dishwashers first made the transisiton from impellers to washarms, a lot of manufacturer's favored large openings because they required a less sophisticated filtration systems, so they were less inclined to clog with food. They were not overly good at getting baked on foods, etc of pots/pans because there wasn't "needling" force to pry foods off. There was a lot of "flooding" force which had the disadvange of a lot of mass to knock dishes around.

When you go to smaller holes, you have to go with more holes to get the same mass (amount) of water flowing through over a given length of time.

Maytag was one of the first dishwashers, that I know of, to use needle sized holes. Their wash arms haven't changed much over the years. Very small holes for velocity and they compensate with many holes to allow a larger amount of water to get through for proper flushing away of the loosened soil.

They were ahead of their time with their self-cleaning filtration systems that filtered water effectively enough to allow the use of small diameter holes that wouldn't clog.

Barry

 

[mrcleanjeans]

the hole story

Barry, you are exactly right.Another machine with pin holes was the early 60s Thermador with the TOWER OF SHOWER wash arms,a square tube that extended from bottom to top with 2 large arms off of it that made the whole arrangement somewhat of a giant S,and a self-cleaning filtering system.This was the second US dishwasher with a stainleess steel tub,James was the first, and Waste King, which was the same company as Thermador,followed suit in the late 60s.Waste King came out with DWs in 1955,having a vinyl on steel tub,and was the second major manufacturer with a revolving wash arm,KitchenAid was the first as we all know.In the early 60s, Waste King was the first DW with two full-size wash arms, one under each rack,Hotpoint's Double Decker system in 1958 does not count,since, yes, there was a lower wash arm,but the upper sprayer was a large disc,not a full size arm.Hope this trivia has some interest to some.

 

[kenmore1978]

"When dishwashers first made the transisiton from impellers to washarms, a lot of manufacturer's favored large openings because they required a less sophisticated filtration systems, so they were less inclined to clog with food. They were not overly good at getting baked on foods, etc of pots/pans because there wasn't "needling" force to pry foods off. There was a lot of "flooding" force which had the disadvange of a lot of mass to knock dishes around."

"Maytag was one of the first dishwashers, that I know of, to use needle sized holes. Their wash arms haven't changed much over the years. Very small holes for velocity and they compensate with many holes to allow a larger amount of water to get through for proper flushing away of the loosened soil."

I think Frigidaire with their "Turbo Wash" spin tube was the first to advocate the "needling" effect of their system. One might include Youngstown with the spin tube being vertical instead of horizontal. Those were unique systems back in the day when impellers were the norm

 

[mielepete]

small vs large

When Kitchen Aid made the transition from the KDS17 to KDS18 series machines the 4 way hydro sweep wash arm spray holes were reduced in size slightly. Same orifice shape just a little smaller. Presumably it was to free up some water for the new wash arm they introduced under the upper rack in the KD18. We were lucky to get the last of the KD17's that come off the German production line that was delivered with the new wash arm. The increased spray pressure certainly improved the wash result with difficult to clean items but retained enough water circulation to "flood" off the soils. Of course the Hobart KA always had filter system anyway. It also had the small spray under to clear the filter.

One of the reasons the KD18 machine was such a bomb was they flipped the wash pump inlet over to the underside. I guess to allow the machine to operate with less water in the sump and to drop the pump height. Unfortunately it placed the suction right opposite the drain impeller and soils bypassed the filter up beside the pump shaft from the drain pump to the wash pump! Crud everywhere in the wash tank at the end of the cycle!!! Kept the KD17! Still going 29 years later.

Pity WP don't build them like Hobart did.

In my own experiments with wash arm sprays the Miele G560 that we use day to day has plastic nozzles in the bottom wash arm that give a wide fan shaped spray. Great for general cleaning but improved greatly when I changed out some of them for the commercial machine needle spray plastic nozzle. Not all of them as you do need the two spray effects - flood and needle jets! Oh and the Miele has fantastic filtration. No blocked wash arm nozzles here.

Love to hear an update on the F&P/KA drawer wash performance with the new wash arm. Get mixed reports on the DDrawers! Great idea but does the execution match?

 

[DADoES]

I washed a casserole a couple days ago, from baked ravioli, 350°F for 45 mins. The baking was done on evening of Sunday 3/27. The washing was done on night of Wednesday 3/30. It came out clean and gleaming except for a little bit of burned residue on one edge, that flaked off with a fingernail.

 

[westytoploader]

Cool! I've put cake pans in the Bosch without rinsing them off (only scraping), and they've all come out spotless. But a baked on casserole is a tougher job...YAY for the DishDrawer!

Which spray arm did you use, since both lift off in a moment's notice?

 

[kenmore1978]

baked/cooked on stuff

Often I will put pots and pans in the dishwasher with no expectations that they will come totally clean. But it at least gets all the excess crud off and like Glenn mentioned it often will take but a few flicks of a fingernail or a light touchup with a scrub pad to finish the job.