Dishwasher leaving residue in random bottles

avatar: LabWrench90656
LabWrench90656
3 posts
Replied to LabWrench90656's post on September 19th, 2012

I have a Labconco washer that started leaving a white residue in random BOD bottles a few months ago.  It hasn't happened in any other dishware or plastic BOD bottles. I Have done all troubleshooting suggested in the manual and by the manufacturer, including using lime-away.  Any other ideas?

avatar: LabWrenchEditor
LabWrenchEditor
1720 posts
Replied to LabWrench90656's post on September 21st, 2012

Are you using LiquiNox phosphate free cleaning solution made for the dishwasher? Or are you using a solid powder type?

Thank you to Mark G for providing this response via LinkedIn

avatar: LabWrench90656
LabWrench90656
3 posts
Replied to LabWrench90656's post on September 21st, 2012

We are using Extran AP 15 provided by EMD, diluted as directed.  It is a sodium hydroxide solution with Nitrilotriacetic acid trisodium salt.  It is phosphate free.

avatar: LabWrenchEditor
LabWrenchEditor
1720 posts
Replied to LabWrench90656's post on September 21st, 2012

I would bet it is either Ca, Mg or Na or salt thereof.

Are you a lab that can test for these?

Do you feed this dishwasher with city water, or maybe well water? Have you checked it for hardness?

City water may have polyphosphates added for corrosion control- could add some complexity into the situation too.

Thank you to Mark G for providing this response via LinkedIn

avatar: LabWrench90656
LabWrench90656
3 posts
Replied to LabWrench90656's post on September 21st, 2012

The city water has hardness of ~14.  They feed orthophosphate.