Heat pumps provide comfortable temperatures throughout the year, but that doesn’t mean they’re perfect. Some of these appliances tick, hum, grind, and click every time they operate. A faulty heat pump typically worsens over time, leading to more problems.
A heat pump makes a clicking noise for the following reasons:
- Bad capacitor
- Stuck debris
- Motor bearing issues
- Temperature fluctuations
- Regular operational sounds
- Fan problems
- Loose components
- Extreme temperatures
- Clogs and internal damage
In this article, we’ll explain all of the possible causes of your clicking heat pump. We’ll also show you a handful of solutions to fix each concern.
Faulty Start Capacitor
According to IERNA Air, a damaged or malfunctioning start capacitor can cause a heat pump to tick. The capacitor is a battery that powers the motor. Whether it’s old, worn, or tilted in an incorrect position, this component can click, tick, and more.
One of the quickest ways to know if the capacitor is the issue is to listen to the motor. A clicking sound in the heat pump’s motor typically comes from the battery area. A slight tick sound at the start of operation is normal, but it shouldn’t persist.
Much like an automobile’s battery, excessive use prevents the heat pump’s capacitor from functioning. After several weeks or months of clicking, the capacitor will fail and prevent the heat pump from activating.
How to Fix
To inspect and replace a heat pump’s capacitor, follow these steps:
- Remove the heat pump’s side panel and locate the capacitor. It should look like a metal cylinder with two to four wires connected to it.
- Use a multimeter to test the voltage going to the capacitor. It should read between 120 to 240 volts, depending on your home’s standard electrical current.
- If the capacitor is below the necessary voltage, turn off the circuit breaker and unplug all of the wires going to the capacitor. You might have to discharge the capacitor if it has residual electricity. To do this, run the heat pump with the breaker turned off for a few seconds.
- Replace the old capacitor with a new one as recommended by the manufacturer. Plug in the old wires, secure the side panel, and turn on the circuit breaker.
For further instructions, review this helpful video:
Debris Stuck in the Pump
Many heat pumps are outside, which means they’re exposed to all sorts of debris. Twigs, rocks, sand, and everything in between can get stuck in the pump. As the air moves through the house, this debris causes ticking sounds. It’s also quite common for the filter to get clogged, broken, or ripped from harsh, abrasive materials.
If your heat pumps filter is broken, it’ll move around when it’s activated. You might also notice the airflow is much worse than it’s supposed to be. Cleaning the filter is sometimes enough to solve this common problem. However, we’ll discuss a couple more useful solutions below.
How to Fix
Clearing the debris from your heat pump can make a big difference. Try some of the following suggestions:
- Clean the inside of the heat pump’s control panel weekly to remove sticks, leaves, dust, etc.
- Open the fan’s assembly and dislodge any debris as quickly as you see it.
- Hire a professional for annual maintenance and cleanings (they can handle the in-depth work while providing a much-needed warranty on the service).
- Dry the heat pump’s exterior after heavy rain to prevent rust, corrosion, and so on.
- Look for signs of infestation, including mice, rats, snakes, spiders, and other pests that can chew or deteriorate the wires.
Skipping Motor Bearings
Heat pump motors have bearings to limit friction while powering the pump. As the bearings get older, they stick and grind against each other. Moisture from rain or humidity can rust and corrode the bearings, too. Unfortunately, motor bearings can also cause grinding, screaming sounds as they worsen.
Breath Healthier Air explains most motors need to be replaced, especially once the bearings make clicking or grinding noises. To replace the bearings, the motor has to be dismantled. Most of the parts are soldered or permanently installed, making them difficult to repair. It’s important to ensure the bearings are the issue before replacing the motor, though.
How to Fix
Unfortunately, it’s highly unlikely that you’ll be able to replace the bearings without getting a new motor. Motor bearings sit inside of the motor, rolling with the non-stop motions. However, these tiny metal balls aren’t sold separately. The grinding worsens and leads to an inevitable replacement of the motor.
Try this process:
- Turn off the electricity going to the heat pump.
- Unscrew the four (or more) bolts holding the front panel onto the unit.
- Locate the motor underneath or behind the fan, depending on which model you have.
- Disconnect the wires and bolts going to the motor, then attach the new motor to the same wires and bolts (always use a manufacturer-recommended motor for safety and efficiency).
- Mount the panel onto the heat pump, turn on the electricity, and test your work.
Significant Temperature Changes
Heat pumps are primarily made of metal. When metal expands and contracts, it makes various sounds. These noises are accentuated by wide temperature fluctuations, such as freezing nights followed by warm mornings. The sun hits the frozen pipes and panels, causing them to click and tick for an hour or so.
The good news is that there’s no reason to be concerned about this common problem. After all, it’s an expected process that doesn’t damage the heat pump. However, the noisiness can be frustrating. We’ll provide a handful of ways to manage the clicking sounds caused by temperature changes below.
How to Fix
If you have pipes running outside of the house, you can use foam insulation. You could use the Dualplex Foam Insulation Roll to wrap exterior pipes, limiting temperature changes and unwanted noises. This 3” x 10’ x ⅛” roll also preserves the pipes by reducing expansion and contraction while improving the heat pump’s temperature control.
Note: Never insulate or cover the heat pump’s motor, capacitor, fan, or control panel. These parts can overheat and cause all sorts of problems if they don’t have enough ventilation (which is another reason regular cleaning is necessary).
Normal Operation
It’s important to remember that almost all heat pumps click a little bit when they activate. These are signs of normal, expected operations. The capacitor clicks while it starts, but these sounds should go away after a few minutes. If the noises persist, it’s likely due to one of the other explanations listed in this article.
Much like the aforementioned temperature fluctuations, clicks and ticks caused by normal start-up settings aren’t a cause for concern. As long as they fade away and don’t turn to grinding, screeching sounds, the heat pump is likely going through its normal operations.
How to Fix
If your heat pump clicks for a couple of seconds or minutes when you turn it on, there’s nothing to worry about. Many heat pumps make various noises when they start. It’s likely a combination of the start capacitor, temperature changes, and fan running. When this process happens, nothing needs to be done.
Obstructed Fan Movement
Heat pumps use fans to circulate cold and warm air through the vents. If the fan is blocked, bent, damaged, or loose, it’ll undoubtedly cause strange noises. The fan’s blades can click against the edge of the heat pump, slowly wearing down the edges. Not only does this process get noisier, but it also damages the fan and heat pump.
The circulation fan can be damaged by rust, improper handling, bad installations, and time-torn components. Whatever the cause is, it’s essential to replace or fix the fan as quickly as possible to limit the potential damage. Routine maintenance is an excellent way to start, but we’ll show you some additional tips, too.
How to Fix
Here’s what you should know:
- Heat pump fan components can rust, including the bolts, fan blades, and motor connections. Use a rust inhibitor, such as Rust-Oleum, to treat and prevent rust.
- Replace the fan if there are any broken, dented, or damaged parts. All you have to do is turn off the breaker going to the heat pump, disconnect the fan’s bolts and wires, and replace it with the same make and model.
- Remove dirt, rocks, twigs, and other debris from the fan when the power is off. This debris can break the fan and lead to overheating.
- Ensure the fan is the proper size. If the fan was recently replaced and it’s louder, makes a clicking noise, or grinds, there’s a high chance that it’s too big or small. Always refer to the brand’s guidelines.
Loose Heat Pump Parts
Loose screws and other components can lead to clicking noises. The rattling parts tick against the metal panel, echoing through the house. It’s not uncommon for old, worn heat pumps to have all sorts of loose parts. This issue also happens when improper parts are installed to replace other pieces in the heat pump.
Airco Mechanical states how common it is for loose parts to be the culprit. The longer they go unchecked, the louder the sound will get. There’s also the risk of screws falling out, rusting, or stripping when you screw them back into place.
How to Fix
Tightening the heat pump’s parts will prevent them from losing efficiency, falling off, and making unwanted noises. Most components can be tightened with screwdrivers. Below, you’ll find a list of parts that should be tightened monthly on your heat pump.
- Front panel (rattling can be disruptive)
- Fan assembly
- Motor mounting bolts
- All wires leading to and from the control board
- Exterior pipes (if applicable)
- All nuts and bolts on any indoor heat pumps
- Ground or wall mounting bolts on outdoor heat pumps
We also recommend hiring an expert to inspect and tighten or reseal HVAC pipes from your heat pump annually. This precautionary step can prevent leaks, utility bill increases, mold, mildew, and structural damage.
Operating Outside the Temperature Range
Checking your heat pump can make a world of difference. Not all heat pumps are rated for the same temperature range. If your heat pump is below or above the manufacturer’s recommended range, it’ll undoubtedly malfunction. Clicking, ticking, and thumping are common symptoms of a heat pump that’s working too hard.
Many heat pumps include air conditioners for warm climates. Turning on the AC when it’s too cold can cause the coolant to freeze the outside pipes. Frozen pipes tick, drip, and cause blockages. As we mention later in the post, blockages lead to clicking noises that echo throughout the area.
How to Fix
Any heat pump operating outside of the manufacturer’s guidelines is prone to overheat, malfunction, and long-term damage. The motors, fans, capacitors, and other components work harder than they should when they’re too hot or cold.
If you have a heat pump, it’s always a good idea to check how cold or hot it can be while running. Never use it outside of the recommended range. However, the previously mentioned pipe insulation can prevent the pipes from freezing, allowing you to use it at slightly colder temperatures than usual.
Blockages and Corrosion
Corrosion and built-up debris can tick and click when they hit against the edge of the heat pump. Rust and corrosion naturally develop from humidity, sprinkler systems, hoses, and so on. Regular professional maintenance is crucial if you want to prevent long-term corrosion, blockages, and so on.
Although they’re some of the easiest problems to fix, blockages and corrosion can quickly become expensive.
How to Fix
The aforementioned use of rust inhibitors goes a long way. You can treat and prevent rust and other forms of corrosion to prevent long-term damage to your heat pump. Blockages in pipes, fans, and other areas of the heat pump cause rattling. These sounds can seem like clicking, ticking, bumping, and so on. Remove them by hand as soon as you see them.
Steve Rajeckas is an HVAC hobbyist with an avid interest in learning innovative ways to keep rooms, buildings, and everything else at the optimal temperature. When he’s not working on new posts for Temperature Master, he can be found reading books or exploring the outdoors.