The outdoor units of heat pumps do make some noise. The sound rating of a heat pump is an indicator of the sound level of the outdoor heat pump unit, and is measured in bels. The lower the sound rating is, the quieter the unit will be.
It is generally recommended to select a heat pump with an outdoor sound rating of around 7.6 bels. The amount of noise will depend on the make and model of the heat pump and how it is installed. Ask your installer to take noise-dampening measures such as using noise-dampening mounts or pads. It’s also important to consider where the heat pump is installed on the outside of your home. Some local governments have restrictions on the placement of heat pumps.
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