Why Is My Space Heater Crackling? 3 Main Explanations

Space heaters make all sorts of noises. My space heater crackles and shifts every time it’s being used, but that doesn’t mean something’s wrong with it. However, some space heater noises can be problematic. It’s always smart to inspect your space heater if it makes new and unexpected sounds.

Your space heater is crackling because the metal is expanding and contracting due to rapid temperature fluctuations. Furthermore, a two-way relay system will click every time the space heater attempts to maintain the desired temperature. Occasional space heater crackles are rarely problematic.

While it’s nice to know your space heater is likely in good condition, it’s important to figure out what’s causing the unknown noises. Below, you’ll learn all about the causes, solutions, and preventative steps for crackling space heaters.

Why Do Space Heaters Make Crackling Noises?

Space heaters can sound like popcorn from their odd crackling sounds. If your space heater crackles non-stop, it could be an electrical problem. However, random pops and crackles usually mean the space heater is maintaining the operational temperature.

Thermostat Sounds

High-end space heaters have relay systems that let you maintain the temperature. While most space heaters use knobs to blast heated air throughout the room, some of them have built-in thermostats. These thermostats click on and off as the temperature hovers around whatever temperature you chose. Since area rugs make rooms feel warmer, they can shift the thermostat more often.

Electrical Connection Problems

One way to know if your space heater’s crackling sounds are causes for concern is to figure out how long it takes for them to start. If the space heater makes weird noises right when you turn it on, there’s likely an electrical problem. Metal expansion often takes a few minutes (sometimes up to 15 minutes) to take place. Faulty motors can also cause crackling noises in space heaters.

Metal Expansion and Contraction

Space heaters have metal grates. These grates hold a lot of heat, but they also regulate the airflow coming from the internal fan. Since the temperature of metal changes rapidly with nearby sources, it’s no surprise that the grates get extremely hot after being a bit cold. This process causes the space heater’s metal grates to click, pop, and crackle.

Check out this helpful YouTube video to learn more about why your space heater is making all sorts of unexplained noises:

How to Fix Space Heater Popping Sounds

To fix a space heater that makes popping sounds follow these suggestions:

1. Store the space heater in a warm location to prevent temperature fluctuations. Since a lot of space heater crackling noises come from expanding and contracting metal parts, you can keep it warm to prevent these movements. Let the space heater cool down before storing it, though.
2. Ensure the space heater has solid electrical connections when you’re using it. Much like an overheated tower fan, your space heater can catch on fire if it has loose wires or plugs. These components can loosen and cause unwanted electrical arcing.
3. Never leave the space heater on for longer than a few hours. Most manufacturers will tell you not to use a space heater longer than one to two hours. Check the user’s manual to know the space heater’s optimal run time. If it’s on for too long, it’ll pop and crackle.
4. Keep your space heater on a flat, stable surface. If the space heater’s heating element is unbalanced, it’ll have trouble heating the grates. The popping sounds will shift the grate and cause metal expansion. Use a leveling tool if you’re unsure if the space heater is flat.
5. Remove dust and debris from the space heater. SMO Energy explains debris clogs can produce strange noises in your heating system. Whether you have a space heater or a whole-house heater, proper cleaning and maintenance are irreplaceable.

If your space heater won’t stop making weird noises, it’s time for a new one. Your space heater can overheat and catch on fire, both of which cause expensive repairs.

I’ve used the GiveBest Portable Space Heater for over a year and it’s working phenomenally. This compact 1500W space heater has a helpful handle that lets you move it, regardless of its temperature. It also has an adjustable heating knob. I love the fan speed knob that helps me heat my room in a few minutes.

Should You Worry if Your Space Heater Crackles?

You shouldn’t worry if your space heater crackles from metal expansion or thermostat temperature changes. That being said, the noises shouldn’t get louder or more frequent. If you notice a change in the sounds, new noises, overheating, or strange smells, turn off the space heater immediately.

It’s often difficult to diagnose electrical issues with space heaters. They have plenty of internal components, most of which are sealed to prevent you from accessing them. Keep in mind that working on your space heater could void the manufacturer’s warranty.

Follow this process to replace the motor or loose, damaged wires:

1. Unplug the space heater and let it cool down to room temperature.
2. Remove the retaining screws, then pull off the space heater’s face plate.
3. Squeeze and pull to gently remove the wires from the motor (most space heater motors are cylindrical).
4. Remove the motor screws, then locate the part number on the motor to order a new one directly from the manufacturer.
5. Connect the screws to seal the new motor inside of the space heater, then connect the wires and face plate.

Not all space heater companies sell replacement parts. You might have to send your unit back to the company to have them test and replace the components. Once this happens, it might be a better idea to replace the space heater. They last a few years and don’t require too much maintenance, so why not get a new one?

Much like using a tower fan in a bedroom, space heaters can be perfect for adjusting the room’s temperature and comfort. However, I suggest using one appliance at a time. Most space heaters have internal fans, so you don’t have to worry too much about a lack of airflow.

In Summary

If your space heater is crackling, you usually don’t have to worry about replacing it. It’ll function properly as long as it’s clear of debris and operating on a level surface. Remember not to run your space heater longer than a couple of hours in a row.