A garbage disposal runs with the help of a motor and sometimes it overheats. A friend of mine was really worried when his disposal did this, and he asked me if a garbage disposal can catch fire.
A garbage disposal can catch fire if it is stuck and the reset button failed to work. This causes its motor to overheat which can technically lead to a fire hazard. But this rarely happens and the most you will see is some smoke rising from the disposal.
I never heard of anyone saying their garbage disposal is on fire, so I was inquisitive when my friend asked. Browsing the internet led me to a 10-year old video that showed footage of an apartment burning due to a fire from a garbage disposal unit. Here’s the video;
There was also news of a recall from the company InSinkErator because some of their models posed a fire hazard due to water overheating the power module and outlet beneath the sink (Source).
What causes a garbage disposal to overheat and catch fire?
Even though garbage disposals are known to overheat, they rarely catch fire. Here are a few possible reasons why your disposal, if you are so unlucky, can catch fire;
Your garbage disposal is stuck
A garbage disposal works using an impeller which helps to break down food wastes. But the free movement of this impeller can be obstructed by jams or any hard objects. All garbage disposals come with a built-in circuit that breaks the electrical connections to address such scenarios. But if you are unlucky, this circuit can fail to trigger, causing the motor of your disposal to overheat and burn out. This overheating can lead to fire hazards in rare cases.
In most cases, you will get ample time and warning to switch off the disposal before it leads to any serious damage. If your garbage disposal stops running and you hear a humming sound coming from its motor, it means the disposal is stuck, and its safety mechanism failed to trigger. If this happens, switch off the disposer immediately and unjam it (here is a detailed guide to unjamming a garbage disposal).
If the safety mechanism worked, it would just stop working without making that humming sound. In that case, you can reset it to work again after removing the obstruction.
Water leaking into the motor
It is not unheard of garbage disposals leaking. A garbage disposal’s motor and electrical circuits sit below its grinding chamber. There is a waterproof sealing between the motor and the grinding chamber to prevent any water from damaging the former. However, the grinding chamber can corrode and have holes, causing leaks. This can lead to fire hazards.
Overheating and fire hazards can also happen due to manufacturing defects in the garbage disposal. These defects can cause its motor to overheat and burn.
Not enough water when grinding
You should run plenty of water while running a garbage disposal. This helps to wash away the food as it is ground. If there is not enough water, the food can accumulate inside the disposal, causing the blades to jam and eventually leading to fire hazards.
Overloading the disposal
Overloading your garbage disposal by cramming lots of food wastes into it at a time can add extra load on its motor. This will cause the motor to overheat and lead to you know what. This can also happen if you try to grind foods that are not garbage disposal friendly.
What to do if there is a fire hazard?
In the infrequent event that your garbage disposal catches fire, disconnect it from the mains. You probably cannot disconnect it from the power outlet because the outlet usually sits beside the disposal, and trying to reach there can endanger you. So the best option is to switch off the mains.
At no event shall you try to extinguish the fire with water. The best option is to use a fire extinguisher. Electrical fires are Class C fires, so you will have to use a suitable fire extinguisher. You can also try to smother the fire using baking soda, an active ingredient in fire extinguishers. But this can be impractical; since your disposal is suspended from the bottom of the kitchen sink, you cannot effectively pour baking soda over the fire.
It can be really tempting to handle the fire yourself but calling 911 is the best thing to do. You will also have to evacuate everyone.
Can you repair a burnt garbage disposal?
Overheating of the garbage disposal doesn’t lead to long-term problems if you handle it well. If your disposal overheats, kill the power and let it cool. Then reset it using the reset button under the unit. Here is a detailed guide to resetting a garbage disposal for your reference.
But if you see smoke rising from the garbage disposal, it is doubtful that it can be repaired. In most cases, it is cost-effective to replace that unit with a new disposal. Repairing the old disposal can cost as much as a new one, and there is no guarantee that the problem won’t come back again.