Have a noisy house or is the dryer next to the bedroom? Keep the noise level of a dryer in mind. The noise level is expressed in decibels. The lower the number of decibels, the more silent the heat pump dryer is. We qualify a dryer with a noise level of up to 64dB as a silent heat pump dryer. You can see the number of decibels on the energy label of the heat pump dryer.