Cloudy glasses from dish washer even when salt full

[google]

Hi,

I've recently changed from using cold hard water in my dish washer to hot hard water from the combi boiler, and everything was fine for the first month.

Now I'm getting extreemly cloudy glasses and even the plates feel rough. I've topped up the salt and rinse-aid but its not had any effect. What does work is adding lemon juice before doing an extra final rinse( which proves its hardness, but 10ml isn't completely effective and its a pain having to do so. Surely, the dish washer salt should be removing the hardness.

Is the problem that I'm heating the water before softening it? am I using the wrong type of salt? or is there something else wrong with the dish washer?

Ken.

[Joseph Meehan]

I don't think that would be a good idea. Why is it set up that way?

[google]

Hi Joe,

a) Using hot water reduces the cycle time from 90minutes to 45minutes b) More importantly it reduces the fuel bill as the natural gas used by the combi boiler is probably about 10 times cheaper than the electricity used by the dish washer to heat the water

PS: The salt I'm using is Granulite made by British Salt (99.9% NaCl) which is available from the warehouse at less than 40=A2/Kg (I paid =A35 for 25Kg).

Ken.

[jackson]

a) Using hot water reduces the cycle time from 90minutes to 45minutes b) More importantly it reduces the fuel bill as the natural gas used by the combi boiler is probably about 10 times cheaper than the electricity used by the dish washer to heat the water

PS: The salt I'm using is Granulite made by British Salt (99.9% NaCl) which is available from the warehouse at less than 40¢/Kg (I paid £5 for 25Kg).

Ken.

Why would you run hard water through your water heating device and ruin that?

[BobK207]

Ken-

Based on my experience with hard water & dishwashers......... in SoCal

I think you're getting a buildup of hard water deposits that sre just being disolved & re-deposited on your glasses & dishes.

In one home I did not have a water softener (very hard water) & every few months I would run a calcium / de-lime agent in the diswasher to get rid of chunks of calcium in the dishwasher.

In the other home I had a water softener that feed the water heater so dishwasher was fed hot soft water..........never had a clouding problem.

I would suggest re-routing the water so the water is softened before being heated.

One further note........very soft water & excessive dishwasher detergent can set up conditions to etch glass.

Can you remove the cloudiness on the glasses with a de-lime agent or is it permanent? If permanent it might be etched rather than hard water deposits.

cheers Bob

btw what does the salt do?

[Walter R.]

Strong dishwashing detergents will etch glass fairly rapidly. Try using less detergent. The etched glass cannot be restored. See CR ratings on dishwasher detergent, especially the column on etching.

[Joseph Meehan]

I would assume you would heat the water before the washer, but your statement was:

"Is the problem that I'm heating the water before softening it?"

Why are you heating it before softening it?

[google]

Hi,

The reason for heating the water first, is that I don't own a water softener nor water conditioner, so the only softening device is the one which is built-in to the dish washer itself.

Trying to remember high school chemistry, I believe that soft water contains CaHCO3 which when heated precipitates CaCO3. The dish washer's built-in softener works by some sort of chemical reaction with NaCl. Is it that the NaCl can only react with CaHCO3 and that by the time its precipitated as CaCO3 the NaCl can't react with it?

How much lemon juice should one add to UK-size standard 60cm free-standing dish washer to remove to chalk on the final rinse? 2 teaspoons is not enough, would a tablespoon be required or more?

Ken.

[Joseph Meehan]

Oh, I see. That makes sense. What does your dish washer say about water supply. Does it specify using cold water? Does it say anything about using hot water?

[BobK207]

Ohh! I thought you were putting the salt in the dishwasher!

Now it makes sense to me!

The salt is to make the recharge brine for the water softener......via ion exchange a softener echanges Na ions for the hard water Ca & Mg ions

I used to de-lime my dishwasher ~ every month using CLR (a delimer available in the states) or you could use a cup of white vineger in the rinse.

SInce you've got a built in softener you may have etched the glasses by the water being soft

cheers Bob

[Banjo]

Hi,

The dish washer manual says its OK to heat the water up to 65C and the boiler output is only 60C, so thats OK.

However, I posted the same question on sci.chem and Ron tells me that I've probably broken the softener by forgetting to keep the salt topped up :-(

Thanks for the amount Bob: 1 cup of white vinegar.

Ken.

[BobK207]

Ken-

I doubt that the softener is broken.......

The ones I've had contained little resin beads, the beads contain the ion echange material. The salt is used to make a brine solution to "re-charge" the beads.

With no salt in the system you'd be "re-charging" with fresh water. I have a little more faith in the robustness of the softener that running low on salt won't kill it.

Let us know how it all works out......whether it was a hard water problem or was the glass etched by soft water & detergent.

cheers Bob

[Banjo]

Hi Bob,

The dish washer is working again. It appears to require about 5-10 full cycles to re-charge the built-in water softener after you've neglected it enough to completely run out of salt. :-)

Thankyou to you and everyone else who helped.

Ken.