The technology of FDM printing, which makes up for the majority of consumer 3D printing, is made possible by thermoplastics and the usage of high temperatures, where 3D printers melt the plastic by generating high degrees of heat to mold them into the desired form.
On the other hand, the high temperatures that a 3D printer uses to conduct the printing process can be as dangerous as they are required, which is one of the reasons that it’s never recommended to leave a 3D printer unattended while it’s operating, similar to cooking food on a stove.
In today’s article, we will be talking about the thermal runaway issue, which is one of the worst things that can happen during the 3D printing process due to the high temperatures involved, and what causes them, particularly in the case of an Ender 5 3D printer, one of the most popular 3D printers currently available.
So, what can cause a thermal runaway on your Ender 5 3D printer?
Below, we have listed the most common culprits that can cause a thermal runaway to occur on an Ender 5:
- Malfunctioning thermistor
- Malfunctioning heating cartridge
- Loose or misplaced thermistor
- Loose or misplaced heating cartridge
- Damaged thermistor wire
- Damaged heating cartridge wire
Next up, we will be analyzing the factors that can cause a thermal runaway on an Ender 5 in more detail, discuss how to prevent a thermal runaway from occurring, and finally, find out whether the Ender 5 comes with thermal runaway protection by default.
Table of Contents
What Can Cause Thermal Runaway on an Ender 5 (Pro/Plus)?
A thermal runaway is one of the most severe issues that you can face in your 3D printing journey, as it essentially means that the 3D printer has lost control of the temperature regulation, which may end up with catastrophic results such as a fire on the 3D printer, or even around its environment.
Here are the most common factors that can cause a thermal runaway on your Ender 5, alongside descriptions that explain the reasoning:
- The thermistor is malfunctioning. A malfunctioning thermistor will falsify the temperature readings and cause the temperature data to be transmitted wrongly to the firmware, which can cause a thermal runaway in the cases where the actual temperature is higher than what the thermistor conveys.
- The heater cartridge is not operating as intended. A heater cartridge that isn’t operating as intended can end up reaching a temperature level that is way more than intended, which can create a thermal runaway in cases where the temperature reaches dangerous levels.
- The thermistor is loose or improperly positioned. A thermistor that is fallen out of its place or is not correctly secured to its slot won’t be able to accurately read the temperatures, which will cause the firmware to have incorrect data about the actual temperature levels that the hotend is reaching. As a result, the firmware will increase the temperature even further, creating a thermal runaway situation.
- The heating cartridge is loose or incorrectly placed. Similar to the thermistor, the heating cartridge also needs to be secured to the correct place, and in cases where it’s mispositioned due to any reason, the temperature readings of the thermistor will be heavily thrown off. In more severe cases, the heating cartridge can end up coming into contact with some other part and directly cause it to catch fire.
- The thermistor wire is damaged. A damaged thermistor wire can cause the connection between the thermistor and the firmware not to be accurate, and in cases where the firmware thinks that the temperature is lower than it actually is, it can end up attempting to heat the heating cartridge even further and create a thermal runaway scenario.
- The heating cartridge wire is compromised. Similar to a damaged thermistor wire, a compromised heating cartridge wire can cause the signal not to be transmitted correctly to the heating cartridge, which can end up with the heating cartridge getting way hotter than optimal.
How to Prevent a Thermal Runaway on an Ender 5 (Pro/Plus)?
Taking the necessary precautions to prevent a thermal runaway from occurring should be one of the first things on any 3D printing enthusiast’s checklist, as safety always comes first.
Below are the precautions we recommend taking to prevent a thermal runaway from ever occurring on your Ender 5:
- Maintain the thermistor frequently. Ensuring that the thermistor is sitting in the correct spot with the screw tightened enough to hold it securely in its place and that the thermistor wire is in good condition now and then will play a vital role in preventing a potential thermal runaway.
- Maintain the heating cartridge frequently. Similar to the thermistor, making sure that the heating cartridge is also sitting in its correct place without any wobbling and inspecting the wire for any potential damage is the best way to rule out the heating cartridge becoming an issue.
- Activate the thermal runaway protection feature of the firmware. The thermal runaway protection feature constantly compares the temperature data that comes from the thermistor against calculated temperature values to find out whether there are any inconsistencies in the temperature readings and immediately shuts the 3D printer off when such a mismatch is detected.
- Secure the area around your Ender 5. Keeping a fire extinguisher handy, ensuring that your Ender 5 is not located in a place where it can get especially hot (room with no ventilation, next to a heater, etc.), removing any flammable materials from the space that your Ender 5 is operating in, and installing a smoke alarm are some of the things you can do.
- Avoid leaving your Ender 5 unattended as it runs. Keeping an eye on your Ender 5 as it runs is the best way to ensure that an unfavorable situation does not occur, including a thermal runaway, as you will be able to intervene quickly and prevent any potential danger.
Does the Ender 5 (Pro/Plus) Have Thermal Runaway Protection by Default?
Utilizing thermal runaway protection is the safest and most straightforward method to ensure that a thermal runaway never takes place, which makes it vital to ensure that the thermal runaway protection feature is active on your 3D printer at all costs.
Since the status of the thermal runaway protection entirely depends on the firmware having the feature and the feature being explicitly enabled through the configuration of the firmware, it’s not exactly possible to say whether your Ender 5 would have thermal runaway protection by default.
As a result of the status being decided by the firmware, it’s even possible for some Ender 5’s that ship with a different version of the Creality firmware not to have the thermal runaway protection enabled by default, while the others do, which creates a lot of ambiguity.
Because of this, we highly recommend flashing an up-to-date version of Marlin firmware to your Ender 5, where the thermal runaway protection feature is automatically enabled in the default configuration, which will ensure that you aren’t leaving anything to chance.
While a thermal runaway is a very critical issue with severe consequences, as the potential culprits behind it are entirely temperature-related, the process of pinpointing the root cause and performing the necessary maintenance is more straightforward compared to many other problems.
To quickly recap, a thermal runaway on your Ender 5 will usually result from one (or both) of the components responsible for the temperature regulation (thermistor and heating cartridge) not working as intended, whether it’s a malfunction, problems with wiring, or something as simple as mispositioning.
As a thermal runaway is a severe issue that can have catastrophic consequences, it’s vital to take the correct precautions to ensure that it does not happen under any circumstance, such as enabling the thermal runaway protection feature and keeping a close look at your 3D printer at all times.
Mike started his 3D printing journey with the Anet A8 when it first came out back in 2017, and has been obsessed with 3D printers ever since. Nowadays, he primarily uses his Ender 3 to print functional parts that make his life more convenient whenever possible.