Report on the CECED dishwasher ringtest - Institut für Landtechnik ...

3.4 Minutes of the final evaluation meeting CECED DW Ringtest
• Cleaning performance of R on different items show big differences between
labs. It was proposed to define individual cleaning performance limits for the
reference machine depending on the kind of items (glass, cutlery, crockery)
(S)
• Especially the cleaning performance of the milk in glasses seems to vary a lot.
It was proposed to collect individual data from all laboratories (pictures and
rating according to colour scale) of glasses before and after drying in the oven.
(A: Proposal for collection by N. Gaudiano, collection and comparison by Uni
Bonn)
• Cleaning of glasses showed increased spread in laboratories 5, 16, 17 and 19!
• Mrs. Pieper reports about their experience not to keep milk stored in the
refrigerator over weekends.
• Cleaning of cutlery: H is always higher than L, but R shows no clear trend.
Perhaps the separate cutlery basket of R on top of the machine is influenced by
other factors as in normal machines. (A: Miele to analyse influencing factors).
Labs 6, 12 and 16 show extremely high values of 5 for R!
• Cleaning crockery: H is always higher than L, but R is sometimes higher than
H and lower than L in other labs!!!
• Cleaning: Repeatability values for H and L are lower than R when taking
absolute cleaning values, but reproducibility is lower when looking on ratios
(so considering R) (C)
• Repeatability and reproducibility should be calculated also separately for
glasses, cutlery and crockery.
• If possible an analysis of the cleaning results for each type of soil should be
done (A: Pozzi)
• Water consumption: Lab 15 is out of tolerance in R
• Energy consumption: Lab 12 is out of tolerance on R
• There is no obvious correlation of time, water and energy consumption and
cleaning performance of R
• Lab 12 reports too low ambient temperature (??) of R
• Energy in cleaning tests: repeatability is very good, but reproducibility is two
to three times higher! Nevertheless 4% reproducibility is a good value! R has
highest value for % reproducibility (A: Miele to check sources). The tolerance
given in the standard for the energy consumptions should be % drastically
reduced (C, S)
• Drying: Lab 11 is identified as outlier. Also lab 10 and 19 are too high for
L. Drying results of L may be influenced by change in softening procedure,
but no clear indication was found for this in the data. Ambient conditions in
lab 11 and 19 are too low. High variation of L may be also explained by the
lower absolute values as this needs to be done between scoring 0 and 1. While
on better drying machines the scoring of 2 is more easy to identify. A better
differentiation of the drying performance in a 5 glass scale may help (S).
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