If you’re noticing a odor from your heat pump, it’s attempting to tell you that something is wrong. We’ve developed a list of the most commonly encountered six heat pump smells, what causes them and how you can correct them.

  1. Heat pump smells musty
  2. Heat pump smells like fish
  3. Heat pump smells like sulfur
  4. Heat pump smells like sewer
  5. Heat pump smells like burning
  6. Heat pump defrost cycle smells

1. Heat Pump Smells Musty

If your heat pump smells musty, there’s likely mold growing on damp evaporator coils or in the ductwork. This heat pump odor is often called dirty sock syndrome. You can prevent this by scheduling regular heat pump maintenance and air duct cleaning.

2. Heat Pump Smells Like Fish

If your heat pump smells like fish, there could be several things wrong:

  • Overheated motor
  • Wiring problems
  • Plastic components or coating is melting
  • Other mechanical difficulties

Electrical problems are serious, so turn your heat pump system off immediately at the breaker box and contact us at for heat pump repair.

3. Heat Pump Smells Like Sulfur

Usually when you have a rotten egg smell, you’ve got a gas leak. But your heat pump doesn’t utilize natural gas. If your heat pump smells like sulfur, a little animal may have gotten inside it for warmth and died. One of our Ilten's [techs can get rid of the smell by cleaning your heat pump.

4. Heat Pump Smells Like Sewer

As we discussed before, your heat pump is electric, so any rotten egg smells are tied to a gas leak elsewhere. If your heat pump smells like sewer, you might be dealing with a backed-up or broken sewer line. We suggest calling a company that does sewer line repair.

5. Heat Pump Smells Like Burning

You might be dealing with an electrical issue if your heat pump smells like burning, burning plastic or burning rubber. This burning smell can be due to melting plastic on electrical wires. Electrical issues in HVAC systems are dangerous and could lead to a fire. If you notice this smell, turn off your heat pump at the breaker and get a hold of us at .

6. Heat Pump Defrost Cycle Smells

Like we talked about above, a dirty socks smell can happen when your evaporator coils need to be cleaned. You might encounter this smell when your heat pump goes into defrost mode.

It’s ordinary for your heat pump to have to switch on defrost mode during heating season. When the air is much colder, frost can form rapidly on the coils from condensation and interfere with heating. During defrost mode, your heat pump shortly switches to cooling to remove the frost.

Having a Ilten's HVAC technician clean the coils will help eliminate the odor.

Depend on for Your Heat Pump Repair Needs

It can be hard to troubleshoot your heat pump by alone. Your comfort matters to us at Ilten's, so you can count on our experts to assist you when you need us. When you need heat pump repair in that you can depend on, call us at .