Poor Dishwashing Performance with Soft Water?

[westtexman]

My friend recently had a whole house water softener installed by Culligan. He really loves it and frequently tells me I should get one. I was almost convinced until I noticed a major decrease in the performance of his dishwasher after the softener was installed. He frequently hosts dinners at his house, and I almost always help with the dishes.

He has the Whirlpool Model DU1055XTVB which provided pretty good washing performance before the softener was installed. He almost always pre-rinses, but even when he didn't the dishes came out beautifully. He uses the Finish Powerball Tabs without phosphates from Sams. Even without adding phosphates (STPP) the results were pretty amazing.

Now it seems like the dishes aren't getting clean at all. They come out greasy sometimes and if any food is left on a dish (or more specifically a utensil) it is almost like the dishwasher was never run. The first time it happened, I asked him if he forgot to add the detergent as the results were that bad. Isn't cleaning performance supposed to increase with softened water?

One thing I have noticed is that his water pressure is lower since installing the softener due to some strange plumbing in his house. Could this be causing a problem? I didn't figure this would affect the dishwasher as it should fill to the same level even if the pressure is low - right?

Any ideas on what may be causing the problem?

 

[DADoES]

 
Hey, Brian! Long time, no see/hear!

Dishwashers are timed-fill so excessively low water pressure can be a problem.  Have a look at the level next time you get an opportunity, maybe post a pic.

 

[hoovermatic]

I have had a Culligan softener for the last 13 years and have never had a problem with my dishwasher not cleaning properly. If it is down to a timed fill coupled with reduced pressure that might be the problem.

 

[strongenough78]

A friend of mine has a water softener in his house. His dishwasher cleans excellent, and the couple times I did laundry over there, my whites were much whiter.

 

[combo52]

POOR CLEANING WITH A WATER SNOFTNER

Also check the cycle several times by opening the door to see if the detergent-water solution is foaming. Sometimes with soft water you get excessive foaming which can really block any real water action. With soft water it is very important NOT to pre-rinse dishes and NOT to use too much detergent. Doing so will not only cut the life of the DW in half but will also etch and otherwise ruin all your dishes. It probably is not a good idea to use the tablets with soft water as these are designed to work well in not so soft water, and using them may result in overdoing the detergent dosage too much.

 

[ronhic]

It is possible to have water that is TOO soft.....if it takes longer than a few seconds to wash the soap off of your hands, then it is quite possibly too soft.....

 

Personally, I'd suggest that your friend have the softness tested and, if at the 'very soft' end of the scale, have it adjusted back...

 

[laundromat]

Down to the Finish

I have used finish (Also known as Electrosol) for decades and always get great results. My theory is that the water be real hot, I have a tankless water heater and it heats the water up to 160F. The dishwasher is a Sears kenmore (made by Whirlpool) and has the two seperate spray arms and "Quiet Wash" system. I always use the sani setting and the timer will not advance until the water reaches 150F to 170F.I had to remove a lot of sediment that built up in the screan where the intake water comes in.When that happened ( Mine is a convertable/portable ), I had noticed imediately that the water level and incoming water was a lot slower then normal.I think that's why the original owners got rid of it.I went and removed the incoming water hose from underneath and removed the sediment that had built up(yuk!!). What got me was that,evidently, these must have somekind of backwash that takes the outgoing dirty water and,somehow, leaves the ground up residue that eventually blocks the incoming water and / or slows it down.I'm not sure if this is a design flaw in Whirlpool's "Unicouple" hose design or not.I now wonder if it does the same with their built in models. If I were you, I'd check that out too. However, Like what was said earlier here, the lower pressure in the incomming water will definately cause a problem in cleaning results.

 

[tomturbomatic]

The clogging of the inlet screen is more a fault of something like decomposing plastic dip tubes in water heaters or fine sediment in the water supply being trapped at that point. No way would national plumbing codes, which mandate the air gap in the fill line, allow a backflow of used water into the fill line, especially to the other side of the fill valve nor would the water pressure on the inlet side allow such a transfer. When the performance of my Ultra Wash began to decline, it was because the fill valve had gone bad and was not admitting enough water and was easily fixed by replacing the valve.

 

[laundromat]

Thanks again, Tom!The valve was what I checked first.Then I removed the hose at both areas it was connected. the pump and the inlet valve. I could hear the valve humming and assumed it was fine. Then, when I removed the unicouple to check for a blockage in it, I saw all the sedement that had acumulated in the screan. It was mostly old food that had been ground up and grease like gum from what had melted and washed off the dishes and cookware. I scraped it all off with a straight screwdriver and ran some CLR threw a full cycle. It's run fine since then.

 

[tomturbomatic]

There is no connection between the inlet valve and the pump.

 

[bwoods]

I would say that there is a 99.9% chance that your friend's problem is due to a low water fill.

Soft water aids detergents, it does not hinder them. Calcium, and other minerals in water, will combine with detergents and reduce cleanng effectiveness.

Water softeners are designed to take hardess down to virtually zero grains per gallon (= to rain water). There is no such thing as "too soft". Unless a softener is grossly undersized for the hardness level, it will always yield water of zero grains/gallon. That's its job.

Sometimes when installing a softener, deposits in pipes may be disturbed and these floating deposits may accumulate in inlet screens of fill solenoids in the washer, and dishwasher as well as aereator screens in faucets. Soft water may initially also redissolve and/or loosen some deposits in pipes for s short while until equilibrium is reached.

Pull the dishwasher and clean the fill solenoid, for your friend, and I think his problems are solved.

The only other thing I can think of is, yes. there is always a few psi pressure drop when routing water through a softener. The manufacturer's state the amount in their literature and varies from brand and model.

If he is on a well, have him turn up the pressure to compensate. If his water pressure was marginial to begin with, and he has city water he could look into a new water main from the street vlave to the house.

I doubt if this is the problem, but could be if he lives in a very old house. If his house has a very old 1/2 inch main he could upgrade it to a 3/4 main. Most recent house have a water inlet main of 3/4 inch if not a full inch. So if he is a water amin inlet piple of 1/2 to 3/4, he could upgrade to 1 inch. Gaenerally, this is an expensive thing to do, but he would be be very happy with the results.

 

[combo52]

SOFT WATER

I will 2nd Barrys statement that there is no such thing as too soft water, 0 grains is ideal.