6 Common Heat Pump Smells Explained

September 30, 2021

If you’re noticing a smell from your heat pump, it’s trying to tell you that something is wrong. We’ve put together a list of the most common six heat pump smells, what causes them and how you can fix 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 moist evaporator coils or in the ductwork. This heat pump odor is often referred to as dirty sock syndrome. You can avoid 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 a couple of things wrong:

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

Electrical problems are serious, so shut your heat pump system off right away at the breaker box and contact us at 407-477-6319 for heat pump repair.

3. Heat Pump Smells Like Sulfur

Normally when you are dealing with a rotten egg smell, you have a gas leak. But your heat pump doesn’t use natural gas. If your heat pump smells like sulfur, a small animal may have crawled inside it for warmth and died. One of our Osceola Air, LLC [techs can get rid of the smell by cleaning your heat pump.

4. Heat Pump Smells Like Sewer

As we mentioned earlier, your heat pump is electric, so any rotten egg smells are linked 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 recommend contacting a company that does sewer line repair.

5. Heat Pump Smells Like Burning

You might be dealing with an electrical problem if your heat pump smells like burning, burning plastic or burning rubber. This burning smell can be the result of melting plastic on electrical wires. Electrical issues in HVAC systems are serious and could cause a fire. If you notice this smell, turn off your heat pump at the breaker and call us at 407-477-6319.

6. Heat Pump Defrost Cycle Smells

Like we mentioned earlier, a dirty socks smell can happen when your evaporator coils need to be cleaned. You might experience this smell when your heat pump is in defrost mode.

It’s typical for your heat pump to have to turn on defrost mode during heating season. When the air is much cooler, frost can form quickly on the coils from condensation and interfere with heating. During defrost mode, your heat pump briefly switches to air conditioning to remove the frost.

Having a Osceola Air, LLC HVAC technician clean the coils will help get rid of the odor.

Depend on for Your Heat Pump Repair Needs

It can be difficult to troubleshoot your heat pump by yourself. Your comfort matters to us at Osceola Air, LLC, so you can count on our professionals to assist you when you need us. When you need heat pump repair in St. Cloud that you can depend on, call us at 407-477-6319.