Why Does My Fan Heater Spark? (Six Reasons Explained)

There are several reasons why an electric fan heater produces small sparks. This article explains the six most common reasons.

We start with four situations that are usually nothing to worry about, but we have tips to avoid sparking.

If you encounter the last two situations, you should turn off the heater and replace it.

1. Dust Can Produce Brief Sparks

Fan heaters shouldn’t keep sparking for a prolonged period. However, if this is the first time you’ve seen a few sparks that went away, it may simply be due to a bit of dust.

When specks of dust or tiny debris have landed on a heating element that quickly becomes very hot, they can light up with a little sparking.

This will be brief because the dust will burn off in seconds. It is often accompanied by the smell of something burning. This whiff should also go away quickly.


How to avoid dust sparks

This shouldn’t happen very often. However, you may live in a very dusty house!

You can avoid dust sparks by occasionally using a vacuum cleaner at the front of the air vent. Of course, be sure to turn off the heater before you do so.

I don’t recommend using tools to open the main body. These appliances aren’t supposed to be disassembled by the owner.

2. Sparking When The Thermostat Turns Off

You may see a small blue spark when the thermostat turns off. This can be part of normal operations.

Cheap fan heaters come with cheap bimetallic thermostats that regulate the temperature.

When the bimetallic switch turns on and off, it creates an arcing when the contact points make and break the electric circuit.

This arcing may be seen in the form of a small blue flash. You may also hear a small click.

This is nothing to be worried about. However, you shouldn’t confuse this with the next situations we review.

3. Plugging In the Fan Heater Can Generate A Spark

When you put the heater’s plug into a socket, you may see a small blue spark. This is often accompanied with a little popping noise.

This is something to worry about. If the plug doesn’t fit the socket perfectly, it can briefly make and break the contact before it is fully inserted.

That brief breaking of the contact can create an arc. This is what produces the brief blue spark.

However, there shouldn’t be too much sparking at a socket. If you are seeing longer large yellow sparks, then this is probably a faulty socket that you should get checked.

4. Unplugging The Fan Heater Without Turning It Off

Are you in the habit of yanking the plug from the socket without turning off an appliance?

That’s a bad habit you need to get out of! It can also produce sparks that may lead to damaging the plug.

The reason for the sparking is that you’ve created a gap between the prongs of the plug and the contact points while the fan heater is still drawing a current.

Of course, this only lasts for a second. But that’s long enough for a small arc to be created between the gap. The arc in turn fires the sparks.

To avoid this, you should flick the switches on the fan heater before unplugging it.

Some heaters only have a thermostat and don’t have switches. In that case, turn the thermostat to the lowest setting.

5. Buzzing And Sparking From A Faulty Connection

Sparks can also be produced when a faulty circuit has a poor connection.

This is often accompanied by a buzzing sound. You may also have the problem where the fan heater will only blow cold air despite increasing the thermostat.

You should immediately turn off the heater in this situation.

If it’s still within warranty, bring it to the retailer for a replacement. If it’s out of warranty, then it will probably be cheaper to buy a new one than pay for an electrician to fix the unit.

6. Sparks From A Bad Element

We mentioned dust and debris burning for a few seconds, which can produce sparks.

But you may also see a part of the element inside the unit that glows red and sparks for a longer time. This is the sign of a fault in the element.

Turn off the heater, and do not use it again.

I’ll repeat what I said in the previous section. If the appliance is out of warranty, it is usually cheaper to by a new one rather than having a fan heater repaired.

Dean Casey
About Dean Casey

Hi, I'm Dean Casey, the founder and chief editor of HomeHeatingHQ.com.

With over 15 years of experience in the HVAC industry, my passion is helping homeowners achieve optimal comfort and energy efficiency in their living spaces. As a certified HVAC technician and consultant, I have developed a deep understanding of home heating systems, insulation, and energy-saving practices.

I started this blog to provide well-researched, practical advice to homeowners looking to improve their home's heating performance and reduce energy bills. Whether it's comprehensive guides, hands-on product reviews, or expert tips, my goal is to share valuable information with you, my readers.

I enjoy spending time with my family and exploring the great outdoors when I'm not busy writing and researching. I'm also an avid DIYer, always eager to tackle new home improvement projects and share my experiences with you.

If you have any questions or comments about home heating, please don't hesitate to reach out through the contact page on the website. I'm always happy to help!

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