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6 Common Heat Pump Smells Explained

By Aztil –

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  • It is not normal for a home to have weird smells, especially when it has air conditioning and heating. An offensive odor that you can smell throughout the house is a sign of trouble. The good news is that these odors are quite distinctive, and so the cause behind them is relatively easy to identify. Usually, most odors will have a link with one heat pump problem or the other. The sooner you identify them and take corrective action, the lesser the chances of any disruption in your comfort. To make things easy for our clients and readers, here is a list of standard heat pump smells and their causes explained.

    Six Common Heat Pump Smells Explained

    1. Musty Or Stale Odor – When you enter a home or building that has been closed for a long time, the indoor air smells off. The best way to describe it is like that of stuffy and old air or the smell of dirty socks. The reason for this smell is mold and mildew that grow in the damp areas of the home. The most conducive environment for their growth and propagation is found in the heat pump near the evaporator coils. From here, the smell is picked up by the circulating air and dispersed throughout the house, making it stinky. 

     How To Get Rid Of It – Staying on top of the annual maintenance routine is the best way to remove the musty odor. During maintenance, the inside of the heat pump is cleaned thoroughly, which removes all mold and fungus. Once they are clean, there is no reason for the stale smell.

    2. Rotten Fish Smell – The smell of rotten fish is hard to ignore. It is so repulsive that staying indoors becomes an ordeal. Your heat pump will emanate this strong and vile odor when some component (plastic or metallic) starts overheating. Before doing anything else, switch off the heat pump to prevent further damage to the unit. Some of the reasons behind the smell could be:

    1. Problems with heat pump wiring.
    2. Overheating of plastic components or melting of rubber coating.
    3. Mechanical issues.
    4. An overheating motor.

    How To Get Rid Of It – Getting rid of the rotten fish smell is a matter of expert handling. You need an HVAC technician to eliminate this heat pump smell as it involves opening the heat pump and checking its internal parts.

    3. Rotten Egg Smells – Rotten egg smell is like the smell of sulfur. Such a smell comes from the heat pump if there is a dead animal or critter inside the ducts. Often, small animals find their way inside the ducts for warmth and protection and die inside. As their body starts rotting, it releases the offensive smell of decomposition. 

     How To Get Rid Of It – To get rid of the rotten egg smell, call your local HVAC technician. He will clean the heat pump and the ducts, if necessary. Once the body of the dead critter is removed, the smell goes away on its own.

    4. Burning Rubber Or Plastic Smell – If it smells like something is burning, it most probably is. Never ignore such smells. Often an electrical problem inside the heat pump will result in wires burning. Essentially, it is the rubber tube on the wires and the surrounding plastic that starts burning. If you fail to recognize this type of odor, the chances are your heat pump will develop a serious issue and stop working altogether. The other probability, if you are lucky, is that the circuit breaker will trip to prevent further damage.

    How To Get Rid Of It – Only an HVAC technician can help you tackle this problem. He will have to open the heat pump to determine where the electrical problem exists and take remedial action.

    5. Heat Pump Smells Like Sewer – If your heat pump produces a sewer-like smell, do remember, there is a high possibility that the circulating air has picked up the smell from elsewhere. The odor does not always initiate in the heat pump. A sewer-like smell means that somewhere in the house, the sewer line is backed up or broken.

    How To Get Rid Of It – You can eliminate the sewer smell only by clearing the backed-up line or fixing the broken pipe. However, this task can only be completed by the company that deals with sewer lines in your locality.

    6. Burning Dust Smell – A heat pump, like any other heating and cooling system, accumulates dust. Switching it on after a long interval results in a strong burning odor that typically goes away on its own within 5 or 10 minutes.

    How To Get Rid Of It – One way of ensuring that this type of odor does not come at all is by ensuring timely maintenance of the heat pump. If, for some reason, that’s not possible, at least clean the unit thoroughly. Else, allow the unit to run for, say, 10 to 15 minutes, and that should be enough time for the odor to go away. If not, call your trusted HVAC technician.

    Takeaway

    The heat pump is not designed to produce any smells. These are actually indicators of what is happening within the heating and cooling system. Hence, it is necessary to be a little vigilant. Thankfully, most heat pump smells are not a thing of grave concern. Yes, they are disgusting and repulsive and make staying indoors an ordeal, but they don’t spell trouble for the system. The same cannot be said for the burning smells. Our only advice is to let your HVAC technician know of the odors as soon as they originate. They shall take care of the rest.

    Aztil Air Conditioningcan help the residents of South Florida find the reason behind their heat pump smells. Our trained, certified, and experienced technicians will thereafter undertake corrective measures to remove them, so you no longer have to suffer unnecessarily. You can also engage our services for HVAC installations , repairs, and maintenance. We also provide 24/7 emergency services . To book an appointment, call +561-559-2205 .

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Great duct cleaning work performed today. Jordan and Hero were very profesional, productive and attentive. Extremely thorough work was performed.
Ramon was my Technician today. He is a young man [24] who was knowledgeable, courteous, and very quick to solve the problem. An excellent addition to the Aztil family!
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Boynton Beach
Michael King came to do AC maintenance. He was professional, courteous & great at his job. Highly recommend & will request him in the future.
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Dana Dusault was timely courteous and did the job.
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Very good and professional niko
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They were great
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Dana was great, very well experienced at what was needed to be done. If I had a question, he answered to the best of his ability, Thanks again, Aztil. 5stars all around.
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Lax excellent job
Response from the owner:Hi Sam, thank you for your kind words! We're so glad to hear that Lazaro did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
I have had pretty good service from Aztil for the last 4 years as a service contract customer. I called them when my AC stopped working and they sent a tech who replaced a 45/7.5 capacitor in about 15 minutes. He then gave me an invoice and estimate for $375.00. I questioned him on what work he did and show me the part he replaced. He showed me the capacitor and said $375 was the cost to replace it. If you look up the part it only cost $25, even with a service call charge there is no way it should have cost me $375... I am beyond pissed and have tried to call Aztil to speak with someone about it but no one is calling me back. I hope this is not your experience just thought I would share mine

Follow up on this review.... Jack the service manager reached out and apologized for the mistake on the charges and issued a refund. Mistakes happen it's how the company handles them that makes a difference. I am glad they resolved this issue relatively quickly.
Response from the owner:Hello John, Thank you for taking time to provide feedback about your experience with our company. We completely understand your frustration and apologize for any dissatisfaction that may have caused your day. We are eager to discuss this experience with you. Please call our customer service manager, Jack. He can be reached at (561) 202-8726. It is our goal to make sure we resolve any issue we can and look forward to speaking with you.
Lazaro was professional, helpful, and courteous.
Response from the owner:Hi Susan, thank you for your kind words! We're so glad to hear that Lazaro did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
I contacted Aztil Air Conditioning to request service for my air conditioning unit. I spoke to Ronda, who provided excellent service. She was very helpful, friendly, and had clear, professional, and transparent communication.
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Dana did a fantastic job. Explained things to us as he went along and you could tell he understood what the problem was and how to fix it.
Response from the owner:Hi Marcia, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
On July 17th my air conditioning stopped working properly (it was set to 75 but was running at 82) and customer service scheduled a quick date for repair. Michael King was the technician they sent and he was very professional, friendly and explained what was being done. He was very thorough and made sure everything was resolved before he left. I would recommend Michael King for any A/C repair.
The a/c is again running great.
Harvey Meiselman
Boynton Beach FL
Response from the owner:Hi Harvey, thank you for your kind words! We're so glad to hear that Michael did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Juan came to our condo within two hours of me calling the company with a two week water leak that other companies could not fix within the past two weeks. He was therefore probably close to an hour to diagnose the problem, found what he thought was the problem, called me because I am out of town and had friends in the apartment to let them in, and he explained everything extremely professionally and calmly and told me thatafter the weekend since today is Friday they would probably try to get the part that’s needed which was a new ACP pan perhaps and did diagnose other problems. So far, we are extremely happy thank you. Kudos to Juan.
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Jorge Rivera was extremely professional, pleasant, knowledgeable, informative and neat. He answered all of my questions and helped set up the WiFi for the thermostat. I would highly recommend him.
Response from the owner:Hi Judy, thank you for your kind words! We're so glad to hear that Jorge did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Juan , was very knowledgeable, polite, and help me set an appointment for the evening of the same day. He found the problem and solved it and found out that my unit was under warranty for me. I’m so glad for Aztil taking care of me and sending Juan, before I would need a replacement of my entire unit. 5 stars!!!
Response from the owner:Hi Margaret, thank you for your kind words! We're so glad to hear that Juan did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Dana was right on time. The job was very professional and clean. It was a pleasure to work with Dana and would request him to service my AC whenever needed.
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Waited all afternoon for a service technician to arrive. The technician was late, but he was great! The best service check up ever!! Alex Molina is a 5 star tech! We’ve never experienced such a thorough check up!!! Asking for Alex from now on!
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Thank You Aztill. Tino was Excellent, knowledgeable friendly service. Did a Great Job! I would recommend Aztill.
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Excellent service. Requested an appointment this morning and the technician Paul Gross was here early this afternoon. He was very polite, knowledgeable and efficient. Made my day.
Response from the owner:Hi phillip, thank you for your kind words! We're so glad to hear that Paul did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
I had Aztil today come for my annual maintenance the technician Juan was the best technician. He was thorough efficient and explained everything he was doing. He truly gives above and beyond service and is a great asset to the company.
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Alex and Molina were very courteous and professional. My air ducts were cleaned and they were careful to clean and vacuum so as to be certain they could be proud of a job well done.
Response from the owner:Hi Debi, thank you for your kind words! We're so glad to hear that Alex did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Niko was prompt, professional and answered any questions very precisely and courteously. Patiently found problem issues and corrected them. Highly recommend.
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Niko 10/10 customer service!
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Albert Rodriguez did a great job!!!
Would highly recommend him!!!!
Response from the owner:Hi Gary, thank you for your kind words! We're so glad to hear that Albert did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Dana was able to diagnose and fix the problem. With my air c conditioner that two prior technicians could not. He left me with a feeling of confidence in his ability and I would request Dana for any future problems
Response from the owner:Hi Dennis, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Thanks Aztil for many years of service Tino was amazing did a great job on the ac units and was very professional I’m recommend Aztil for any ac needs.
Response from the owner:Hi Jose, thank you for your kind words! We're so glad to hear that Tino did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Dana Dussalt was awesome & very patient & courteous by ensuring our AC was functioning properly & explained in detail the issue that he resolved.
Response from the owner:Hi Sharron, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
ANTONIO MORENO services were a 10 where 5 was the highest!
Aztil is a great company where you can track your service teal time coming to your home. They’re right on time. They explain everything I’m impressed.
Response from the owner:Hi William, thank you for your kind words! We're so glad to hear that Antonio did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Albert is a great technician. He is very clean and courteous. I have been a customer of the company that they bought so it's been like a total of twenty eight years, and i'm very satisfied.
Response from the owner:Hi Mark, thank you for your kind words! We're so glad to hear that Albert did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Niko Garza completed a detailed diagnostic & flush of my home AC. Very professional and courteous. I highly recommend Aztil & Niko
Response from the owner:Hi Michael, thank you for your kind words! We're so glad to hear that Niko did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Paul gross was wonderful.
Response from the owner:Hi Diana, thank you for your kind words! We're so glad to hear that Pail did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Can I please 🙏 say ... a/c was down for about 14 hrs in a day in July 😡 then they sent there top star Danna & my man took care of everything !!!!!! 5 ☆☆☆☆☆
Response from the owner:Hi Darius, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Dana was great very helpful and knowledgeable.
Response from the owner:Hi George, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
I wanted to commend Dana Dussualt for his hard work at rectifying a substantial issue that I had with my HVAC system. It did require multiple visits but he stuck with it and figured out the issue and did get it resolved. Dana spent hours in the attic in the middle of summer working on getting this fixed. He is both a very hard worker and a pleasant individual. Dana is a credit to your company. In addition, the office staff worked with me in getting these repairs done by insuring we would get service on the date promised. Having no air conditioning in the summer is not a great experience. I have been an Aztil customer for many years.
Response from the owner:Hi Lyle, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Dana was on time and knew what he was talking about, highly recommend him.
Response from the owner:Hi Ginger, thank you for your kind words! We're so glad to hear that Dana did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Rhonda answered my call and was wonderful. Dana and Schuyler arrived within the hour and fixed my a/c problem. Cleaned everything up and would use Dana anytime.
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