Both the indoor and outdoor components of a heat pump make some noise. On average, most modern heat pump outdoor units have a sound rating around 60 decibels, equivalent to a moderate rainfall or normal conversation. Some ultra-quiet models attain lower sound level ratings. Heat pump indoor units generally have sound level ratings between 18 and 30 decibels.
Each heat pump system has a different sound level rating. This rating is specified by most manufacturers on the system’s technical specification sheet, and represents the sound, measured in decibels, generated by the heat pump when it is working at full capacity. Noise is created by the fans and compressors. The fan model and speed, as well as the airflow and pressure flow of the system, affects the level of noise that the fan will produce.
Reduce noise by looking for these features when purchasing a heat pump:
- Variable speed fans and compressors
- Soft start and stop functions
- Nighttime/low sound modes
- Insulated compressors
When having a heat pump installed, ask your contractor about the best location for the outdoor heat pump unit and how that placement may impact the noise levels of the system. Best practices call for placing the outdoor unit away from windows and adjacent buildings, and install the unit on a solid base such as a concrete pad or block with a vibration-absorbing mat to reduce noise. Using barriers like fences, landscaping or decks help disrupt the noise transmission to your home as well as your neighbours. Be sure to ask your contractor about any relevant municipal residential noise-control bylaws at different times of the day.
You can compare heat pump noise to the decibel level of common sounds using this chart:
Everyday Noises: Sound Level Rating (dB):
| Rustling Leaves | 10 dB to 20 dB |
| Whispering | 20 dB to 30 dB |
| Quiet Library | 40 dB |
| Moderate Rainfall | 50 dB |
| Refrigerator | 60 dB to 70 dB |
| Toilet Flushing | 75 dB |
| Heavy Traffic | 80 dB |
See the City of Vancouver’s “Heat Pumps & Noise: A Neighbourly Installation Guide” for additional tips and information about how installing heat pumps and minimizing noise.
Once your heat pump is installed, completing regular (annual) maintenance on your heat pump is also important to ensure your heat pump is operating well and not producing unnecessary noise.
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