Miele DGC 6500 Operating And Installation Instructions page 159

Appliance and building-in dimensions
Ventilation cut-outs
To ensure the appliance has adequate ventilation, the following cut-outs
measuring 500 x 40 mm must be provided:
a in the base of the building-in niche
b in the floor of the cupboard space below the building-in niche
The furniture housing unit must not have a back panel fitted behind the building-in
niche.
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