Heat pumps are great alternatives to the regular HVAC heating option, since they can be used throughout the year and can be more efficient depending on the model.
Compared to conventional HVAC systems, heat pumps are used more frequently. Nonetheless, whether you install a brand-new heat pump or use an old model, it’s common for heat pumps to produce strange sounds after a period of operation. From humming to grinding noises, a heat pump makes various noises that can be anything from innocuous to alarming.
Types of Heat Pump Noises
A heat pump can produce a number of different sounds during operation, but not all noises are a cause for concern. Here are the various heat pump noises and what they mean.
1. Noises during startup and shutdown
Start-up and shutdown noises are among the most common heat pump noises experienced by most homeowners. No matter how high-end the model is, every heat pump is supposed to make some noise when switched on, which is absolutely normal. However, these sounds should not last more than two minutes. If you find your heat pump continues to make noise even after that, it might indicate issues in operation which should be addressed ASAP.
2. Banging noises
Banging heat pump noises mainly come from the outdoor unit. These noises occur if there is a loose component or if a foreign object gets stuck inside the unit by condenser fan blades. If you hear banging noises, turn off the unit and check the outdoor unit to spot any foreign objects. You need to remove the covering of the outer unit to access the interior. Remove the foreign object, reinstall the cover and switch on to check.
3. Buzzing or humming noises
When the heart pump is turned on, there are different electrical bits that work together. Buzzing or humming noises come from the working of these small electrical parts, and thus such noises are quite normal. However, if it persists or gets loud, consult an expert to be on the safer side.
4. Vibrations and rattling noises
A rattling or vibrating noise indicates that your heat pump’s outdoor unit has either become loose or uneven or even the mounting foot on the compressor is loose or damaged. You can install a rubber pad below the unit to absorb the vibrations. However, if there is a broken mounting, you need professional help to replace it.
5. Noise from the fan motor
The noise from the heat pump fan motor is typically not an issue. It is usually a consistent and smooth sound that should not be overly loud or bothersome. If, however, the noise becomes excessive, you need to get the fan inspected.
6. Gurgling noises
Funny thing to say, even heat pumps make gurgling noises. But this kind of noise is not at all a good sign. A heat pump makes gurgling noise if there is a refrigerant leak or the refrigerant charge is low. A leak in the refrigerant lines or outdoor coils allows air to enter the components, leading to such noises. Calling an HVAC professional is important, as any refrigerant repairs should only be handled by trained professionals.
7. Swooshing noises
Heat pumps are used for both cooling and heating purposes. During winters or chilly days, the outside unit might freeze, leading your heat pumps to go into defrost mode. It may result in a whooshing noise from your heat pump, which is normal during winter.
8. Squealing noise from the compressor
The squealing noise from the heat pump compressor is a sign of a bigger problem. This can be due to worn-out bearings, loose or damaged parts, or overheating. If left unfixed, it can cause additional damage to the system, increasing repair costs. Thus, it makes sense to call in an HVAC technician at the earliest.
9. Bubbling
Bubbling is yet another loud sound produced by your heat pump system when outside air enters your drain pipe. This usually results from a buildup of air between the evaporator and the condenser of the heat pump system.
In some cases, this can be resolved by simply releasing the air pressure by pushing down on the float switch. If the noise persists, it may indicate a more serious issue, such as a blocked condensate drain or clogged filter. It’s important to have a professional inspect your heat pump system to determine the root cause of this bubbling noise and recommend any necessary repairs.
10. Hissing noises
A hissing noise coming out of your heat pump when everything else is running smoothly generally indicates a refrigerant leak or blocked air filter. However, hissing noises should not be avoided. You need to call a professional immediately for a thorough inspection and get the issue fixed.
11. Clicking noises
You can hear a clicking noise whenever you switch on your heating unit. This noise happens due to contractions of the metal components present inside the system. However, clicking sounds are normal, and there is nothing to worry about.
What should you do if your heat pump is producing unusual noises?
While certain noises such as clicking, buzzing or swooshing are not a matter of concern, a few noises should not be avoided. If you find out that your heat pump has been making unusual noises for quite some time, you should not wait any longer. You need to call a professional HVAC service agency for instant inspection.
HVAC professionals offer fast and reliable repair and replacement services. It is best to call in certified HVAC specialists like Autumn Air Heating And Cooling to inspect the malfunctioning systems when you’ve confirmed there’s a problem. In this article, we’ll cover 11 different noises often experienced by homeowners that use a heat pump and explain what they mean so you can tell when you need a professional to assist.
