Always read the directions on the item completely, and clean according to the instructions before washing a heated mattress pad. The chemicals used in dry cleaning can damage the insulation on the wires in heated mattress pads or heated blankets. Do not iron electric blankets.
Wash heated mattress pads in a home washing machine
Manufacturers in the United States typically allow their heated bedding to be cleaned in a washing machine according to specific instructions. Only wash heated items using a short, gentle cycle selection on the washing machine. Some manufacturers state that heated bedding shrinks slightly and must be stretched back to its original shape after laundering.
Dry clothes by hanging or machine
Most manufacturers allow limited drying in a clothes dryer that is big enough to let the mattress pad tumble freely. Do not use a commercial dryer on high settings because some use very high temperatures that can damage the mattress pad. Air drying is also a good option for those who have the space available.
Repeat as desired
Stubborn stains may require a second trip through the washer or the use of more powerful detergents. The use of a pretreater or degreaser can often help eliminate particularly tough stains.