Heat Pump That Sounds Like Helicopter – What’s Wrong?

Home office is the new trend today, but it’s really uncomfortable to work with crying children, squeaky chairs, creaking stairs and a heat pump that sounds like a helicopter. So, without wasting time, let’s find out the reason behind that noise-making heat pump.

Normal Heat Pump Noises:

A heat pump does generate some loud and strange noises but some of them are completely normal. You see, there are many components in a heat pump and each has its own function, along with its signature noise.

Start-Up and Shut-Down Noise

When you start up a heat pump, you’ll hear a thumping sound, similar to the rattling sound that’s usually generated by an unbalanced washing machine load. Compared to the washing drum noise, the start-up sound in a heat pump is not a result of an imbalance but is produced by a compressor, when the refrigerant goes from liquid to gas. And, you’ll hear the same vibrating noise when the heat pump shuts down. These start-up and shut-down sounds usually last for only a few minutes.

That being said, if you have been using a heat pump for years and you’ve never noticed any weird noise during its normal operation until now, then maybe it’s time to call an expert.

Defrosting Heat Pump

When it comes to energy-efficient heating systems, everyone knows that there is no better option than a heat pump. It does not only transfer thermal energy from the cool outdoors into a warm house but it’s also the best device you can rely on to maintain a pleasant temperature in your house. But what many don’t know is that a heat pump goes through a cycle called the “defrost” mode.

During the freezing season, an outdoor HVAC unit might get cold and the outdoor coil might get covered with ice. When a heat pump activates its “defrost” mode, it will reverse its normal operation routine to go through a cooling phase in order to melt away the frost surrounding the coils; the heat pump will dissipate warm air, eventually warming up the coil and melting the ice. During this process, the heat pump will generate a whooshing and vibrating sound which will only last for some minutes.

Fan Motor Noise

A fan motor is designed to cool the coils of a heat pump and can usually be found at the top of a heating unit. What makes this simple component interesting is the consistent whir noise it produces.

Noise From the Heating/ Cooling Process

There is another sound that can be produced by a heat pump; a sound which you are very familiar with – the common and quiet electrical sound.

When electricity runs through electrical appliances, you’ll hear that quiet buzzing or humming sound. This is fairly normal and most people are attuned to the sound of electricity.

Uncommon Heat Pump Noises:

Although it’s true that compared to other heating and cooling systems, a heat pump makes a lot of noise, there are some sounds to which you should give your undivided attention.

Loud Metal Banging

Have you ever heard the sound a metallic object does when it hits a cement floor? Or, do you know what it sounds like when a metal is hit repeatedly with a hard object? If you hear this kind of noise from your heat pump, it means you need the help of an expert.

There’s a high possibility that a part inside your heat pump has come loose and is constantly being hit by fan blades. Or, maybe a foreign object – with the size of a large chunk of ice – has made its way into your heat pump.

Grinding and Gurgling

These two noises are clear indications that there’s something wrong either with the motor bearings or the coils of your heat pump.

Shrieking Noise

That sounds terribly annoying, but it can happen, especially when the compressor of your heat pump is experiencing way more pressure or stress than usual.