Why Your Heat Pump Smells Like It’s Burning

Why Does My Heat Pump Smell Like It’s Burning?

A burning smell coming from a heat pump is usually caused by one of five potential issues:

1. Dust Is Burning Off After the System Has Been Sitting

This is a common reason for a heat pump to smell when the heat turns on for the first time in a season. Over the past year, dust has likely accumulated inside the system and is now heating up and burning off as the unit starts up again. You’ll know this is the problem if the smell goes away after a bit and doesn’t return until next year.

2. Your Air Filter Is Dirty or Clogged

Another possible cause of a burning odor is a clogged air filter. Because of how heat pumps work, proper airflow is essential for the system to run efficiently and safely. A dirty filter can restrict airflow and contribute to overheating. Turn off the system before checking or replacing the filter, and have a professional investigate any persistent burning smell.

3. An Electrical Component May Be Overheating

A heat pump burning smell can sometimes be caused by an electrical malfunction inside the system. The compressor, fan motor, capacitors, or even the wiring can potentially fail and overheat. This can make the heat pump smell like burning plastic. This is a more serious issue, so we recommend shutting the system off and having a professional inspect and repair it to prevent further damage.

4. The Blower Motor May Be Overheating

If your blower motor is forced to overwork, either due to airflow issues or a mechanical fault, it may overheat and cause an electrical burning smell from the heat pump. If this part of the heat pump is overheating, you’ll need a professional to inspect the unit and perform heat pump repairs to fix the problem.

5. Debris Has Entered the System

Another possible reason your heat pump smells like smoke is that debris has entered the system. This could be household dust, pet hair, small pests, or small amounts of paper or insulation from your home. To avoid this issue, change your air filter regularly and have your heat pump inspected and cleaned periodically.

When Is a Burning Smell From Your Heat Pump an Emergency?

A slight burning odor from your heat pump for a few minutes is likely due to dust and isn’t necessarily an emergency. But if the smell is harsh and acrid, like burning chemicals, rubber, or plastic, it’s an emergency. Heat pump electrical problems often create a more unpleasant burning odor, and running the system can put you at risk of smoke inhalation or even a fire. Shut off the system and call a licensed professional for heat pump troubleshooting.

What Should You Do If Your Heat Pump Smells Like It’s Burning?

If you notice a burning smell from your vents while the heat pump is running, here are the steps to take:

1. Turn off the heat pump at your thermostat if you can do so safely.
2. If you see smoke, flames, or sparks, or suspect a fire, evacuate your home and call emergency services from a safe location. Do not delay evacuation to reach the electrical panel or attempt repairs.
3. Never use water on an electrical fire.
4. If there are no signs of fire and it is safe to remain inside, inspect the air filter with the system off and change it if needed.
5. Do not open the heat pump itself, as it carries a high risk of injury or system damage.
6. Call a licensed repair professional to inspect and repair the system before turning it on again if the odor persists, returns, or smells like burning plastic or electrical insulation.

How a Professional Heat Pump Evaluation Identifies the Problem

Unless you’re sure the HVAC burning smell is caused by a dirty air filter, you’ll need to hire a pro to inspect the system and determine why the heat pump isn’t working properly. Here are the steps a professional will take to identify the issue and repair your system:

1. Your technician will ask about any past issues and look for other signs the heat pump needs repair, such as temperature problems, high energy bills, or strange noises.
2. They’ll inspect the entire system for electrical problems and other malfunctions.
3. Your tech will use a multimeter to test electrical components as appropriate, including voltage and continuity.
4. They will also check capacitors and contactors and measure current draw on motors and the compressor as needed.
5. They test the system’s heat transfer and static pressure to see whether airflow issues are causing the burning smell.
6. They combine all tests and inspections to determine the cause and present their findings and a recommendation to repair or replace the unit.

Repair or Replace? What If the Burning Smell Reveals a Bigger Problem?

In some cases, a burning HVAC smell signals a more serious issue, but repair may still be possible. We usually recommend replacing a system only if it’s more than 10 to 15 years old or if it suffered a catastrophic failure, such as a total compressor malfunction. Otherwise, we can likely repair your heat pump and share maintenance tips to help you avoid further odor issues.

Get Your Heat Pump Checked Before a Small Problem Gets Worse

Whether it’s a slight burning odor, an unusual noise, or warm and cold spots throughout your home, you should never wait to have a heat pump issue checked out. Ignoring these signs can lead to heating inefficiencies, an uncomfortable home, damage to your heat pump, or even a house fire. Professional maintenance can help identify developing problems and reduce these risks. For best results, we recommend having your system professionally inspected, maintained, and cleaned at least once a year to help prevent problems and extend the system’s lifespan.

If you’re dealing with any heat pump issue, the team at Kliemann Brothers is here to solve the mystery and get it running smoothly again. Contact us today to schedule a heat pump service appointment!