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

4 Methodology
CECED DW Ringtest
4.1 Important changes of standard version EN50242:A3
• air humidity tolerance is reduced to (55± 5)%, water hardness shall be 2.5 ±
0,5 mmol/l
• no damage load pieces shall be used, pieces shall be used for 200 ± 20 cycles
• soil application details
• dishwasher operation and assessment details (e.g. to evaluate cutlery last)
Participating laboratories were asked in the first mailing to perform the test for
Energy labelling according to the lastest official version of the standard including
the CECED code of testing. As the latest change of the standard (EN 50242:A3)
did get officialised only by December 1st, 2002, some laboratories may not have
strictly followed this version.
4.2 Soiling
The procedure of soiling the loads for cleaning tests has to be done according to EN
50242, section 6.4. Preparation and application of the soils (e.g. eggs, oat flakes,
margarine, minced meat, milk) is standardised, though the source respectively supplier
of the foodstuff is a recommendation only. Where available, the suppliers
where asked for.
4.3 Soil drying
After applying the soils the crockery undergoes the oven drying procedure for two
hours to simulate stubborn soilings. Since the oven (e.g. see figure 3) drying has a
strong influence on the later test outcomes, model data (see table 5) and temperature
logs have been requested by Uni Bonn. The intial idea to use tempreature
indicator strips was not feasible. However, after communicating the issue with all
participants, a recommendation was issued how to perform the loading procedure.
Glasses (soiled with milk) are put into a microwave to brown the milk. See figure 11
for a graphical comparison of glass cleaning performance. Additional examinations
may be needed at this point.
4.4 Machine loading schemes
Figure 4 shows how the soiled parts have be be inserted into the L machine. Similar
instructions exist for the H and R machines, and are of course available to the
participants.
4.5 Pretests
To assure proper test machine operation, two preliminary cleaning runs without
soils have to be performed, data measured and sent to Uni Bonn for confirmation.
This is done to exclude the possibility to runs test with machines that have been
damaged during the transports.
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