Proline PROHP81 Manual page 65

Levelling the appliance
The dryer must be perfectly level to ensure safe and proper operation.
If the dryer is not properly level, adjust the levelling feet as necessary.
DO NOT insert pieces of wood of any other object under the feet.
If the appliance is installed on a carpeted floor, please adjust the feet in
order to allow air to circulate freely under the appliance.
Do not remove the feet. Do not decrease the floor clearance through
thick carpets, pieces of wood or equivalent. This can increase the heat
which can affect the operation of the appliance.
Level the appliance by raising or lowering the feet.
Never put cartons, wooden blocks or similar materials under the machine to
balance the irregularities on the level of the ground.
Accurate levelling prevents vibration, noise and displacement of the appliance
during operation.
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