How noisy are Air Source Heat Pumps?

Are you considering installing an air source heat pump but concerned about the noise it may produce? Noise can be a significant factor to consider when choosing an HVAC system for your home. Understanding the potential sound levels of air source heat pumps can help you make an informed decision.

Are air source heat pumps noisy?

In general, air source heat pumps can be relatively noisy up close, but this noise reduces significantly with distance. As such, they are typically installed in more secluded locations, so that the sound is not overly intrusive.

Air source heat pumps typically produce between 40 - 60 decibels of noise. This can be considered a low to average level of noise. This noise level is similar to that of a dishwasher or microwave.

It's also worth noting that any fans present tend to be relatively quiet compared to traditional heating systems, such as boilers or furnaces. With appropriate installation and maintenance, there is no reason why systems should cause excessive disturbance.

What does an air source heat pump sound like?

Modern heat pump systems are designed to operate quietly. You will usually only hear a low whirring noise coming from them. This noise is caused by the fan pulling in warm air into the compressor.

It's normal for noise levels to climb, but any rise should be slight. This could indicate that something isn't running correctly and maintenance should be arranged as soon as possible.

Are heat pumps louder in the winter?

It’s common for heat pumps to produce more noise during winter. This is due to the increased strain on the internal components as they work harder to keep your home warm.

Noises can include:

Whooshing sounds: A normal occurrence when the heat pump shifts to defrost mode during the cold season. These sounds may seem louder in winter when the heat pump is working harder.

Loud metal-on-metal noise: If you hear this type of noise, it could be the fan blades hitting chunks of ice or loose components.

Rattling and loud vibration: This could be caused by loose screws or hardware components. Some heat pumps are naturally noisier than others. If the rattling and vibration worsen over time, it's a good idea to have a professional take a look.
Screeching noise: Similar to belts in vehicles, screeching or squealing sounds can indicate a problem with the blower belt or its bearings. Contact a technician for maintenance, repairs, or replacements.

Clicking humming and hissing: Rapid clicking accompanied by humming may indicate electrical issues in your heat pump. Hissing sounds can be a sign of refrigerant or air escaping, which is a major issue.

Noises when turning on/off your systems: If you're a new heat pump owner, these sounds may seem strange. Some heat pumps have components that tap and click when shutting down.

Buzzing or grinding sounds: A buzzing sound could be caused by malfunctioning coils or contacts. Gurgling may indicate low refrigerant levels and a shrieking sound could be due to a dirty motor bearing.

How can I reduce noise from my heat pump system?

Reducing the noise from your heat pump system is possible with a few simple steps. Here are some tips to help you reduce the noise generated by your heat pump:

Location: Properly locate your heat pump system to mitigate noise transmission. Ideally, place it away from windows, bedrooms, and outdoor living spaces to minimise disruption.

Sound barriers: Install sound barriers or acoustic panels around the heat pump to absorb and dampen the noise. These can be made of materials such as foam, rubber, or mass-loaded vinyl. Ensure they are securely installed to create an effective sound barrier.

Vibration isolation: Use vibration isolation pads or mounts to reduce the transmission of vibrations from the heat pump to the surrounding structure. This can help the noise generated by the unit.

Regular maintenance: Keep your heat pump system well-maintained. Properly lubricate moving parts, tighten loose connections, and clean the system regularly. A well-maintained heat pump is generally quieter and more efficient.

Fencing or landscaping: Consider installing a fence or planting tall shrubs or trees around the heat pump to act as a natural sound buffer. These can help absorb and block some of the noise emitted by the unit.

Note that while these tips can help reduce the noise from your heat pump system, some level of noise is typically normal. Heat pumps tend to be quieter compared to other heating and cooling systems. However, there may still be a low humming or fan noise present during operation.

Why is my air source heat pump noisy?

There can be several reasons why your air source heat pump is noisy:

Fan noise

The most common cause of noise in air source heat pumps is the fans. The outdoor unit of the heat pump contains one or more fans that help circulate air through the system. Over time, these fans can become worn or dirty, leading to increased noise levels.

Compressor noise

The compressor is another component in the heat pump that can produce noise. As the heart of the system, it pumps refrigerant and generates the necessary heat transfer. However, older or inefficient compressors can create more noise due to mechanical vibrations or worn-out parts.

Air flow restrictions

If the air intake or exhaust vents are obstructed or clogged, it can cause a higher workload on the fans, increasing noise. Regularly inspect and clean the vents to ensure optimal airflow.

Installation issues

Improper installation can also contribute to noise problems. If the heat pump unit is not securely mounted or properly levelled, it can lead to vibrations and rattling noises. Additionally, loose components or connections can result in increased noise output.

Age and wear

As with any mechanical equipment, age and wear can cause heat pumps to become noisier over time. Bearings may wear down, motors might become less efficient, and parts may become loose, resulting in increased noise levels.

Environmental factors

Lastly, environmental factors such as weather conditions or nearby structures can impact the noise level of your air source heat pump. Wind or rain hitting the unit can amplify noise. If the heat pump is placed close to walls, it can create echoes or vibrations.

Concerned about the noise levels of your air source heat pump? We're happy to answer any questions you may have and provide expert advice on how to reduce noise from your system. Contact us via email at enquiries@Unitherm.co.uk. Get in touch today!