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What Are The Symptoms Of Bad HVAC Transformer

By Aztil –

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 The HVAC system is the heart of your household. It is a machinery which consists of many big and small parts. In machinery as complex as that occurrence of a fault is normal. What is important is that you deal with them promptly and efficiently. The local HVAC company is your best answer. However, being a little proactive, you too should know a little about the things that could go wrong with your HVAC unit. If you have at least some basic knowledge, nobody would be able to fleece you easily. In our bid to educate you about the issues you could face in relation to your HVAC, today we shall deal with the transformer . The transformer of the HVAC unit is also susceptible to developing faults. But how can you be sure of that? This post will help you understand a bit more about transformers and also tell you about bad transformer symptoms in HVAC.

What Is A Transformer?

A transformer is a device which can increase or decrease the voltage of an alternating current or AC. It is a passive device which transfers electrical energy from one circuit to another. This is achieved through electromagnetic induction.

Role Of HVAC Transformers

Transformers are used when the incoming electricity voltage needs to be either raised or lowered to meet the requirements of the other electrical components or parts. The work of a transformer is to change the voltage that travels from the circuit board to the HVAC unit. This progression allows the air conditioner and the fan to work in synergy while cycling on and off. The usage of Electricity can be amplified or diminished depending on how much power is needed.

Where Is The Transformer Located?

In an HVAC unit, the transformer is located inside the furnace. But in a few cases, which is less than 10%, it can be found inside the AC unit situated outside.

Bad Transformer Symptoms In HVAC 

There are a couple of things which are indicative of a bad HVAC transformer. These are –

1. Humming And Vibrating – The humming sound in transformers is normal. It is produced due to the expansion and contraction of the laminations or the iron core. However, if there is a drastic increase in this sound, accompanied by strong vibrations, it is indicative of a bad transformer in your HVAC unit. There could be other possible causes of the humming sound and the vibrations like incorrect installation or a faulty capacitor. So, it is best to let a technician come and check out where the real problem lays.

2. Tripped Circut Breaker – When the transformer of your HVAC unit goes bad, the circuit breaker will usually trip. It trips so that there is no surge of voltage. A voltage surge can fry various parts throughout the furnace and AC causing a major breakdown of the said equipment. 

3. HVAC Not Working – With a bad transformer, your HVAC unit will not work even when it has an adequate power supply. This is a protective mechanism to save the unit from severe damage.

There is no sure-shot way of confirming that the HVAC unit is malfunctioning due to a fault in the transformer. This can only be discovered through the elimination method. The HVAC technician will start with the most probable and simple causes which could prevent the unit from functioning. When nothing else works, they will tackle the bigger causes, one of which being a bad transformer. 

Checking The Transformer Is Bad

Your HVAC unit is not working, and you have worked your way through all possible causes. Nothing seems to solve the problem. It’s time to call in the reinforcements who can validate your findings and look for the real problem. The things you were attributing to a simple problem could actually be bad transformer symptoms in the HVAC unit. In order to confirm that the problem is indeed the transformer, you need to check it. For this, you need a multimeter, as well as the basic knowledge of using it. A faulty transformer gives an infinite or wide-open reading while a transformer without any fault reads between zero to 10 ohms which is indicative of a closed circuit. 

Causes Of A Bad Transformer

Bad transformer symptoms in HVAC unit may appear due to the following reasons –

1. Bad Contactor – More often than not, it is a bad contactor which leads to a blown transformer. A bad contactor puts the entire unit under a lot of stress. When the tension or strain becomes too much for the unit to handle it mostly results in a blown transformer.

2. Wiring Issues – Loose wires or cables inside the transformer can cause a short circuit due to which the transformer may fry.

3. Power Surge – An electrical failure in the form of a power surge can also cause transformer failure. 

Can I Replace The Transformer In My HVAC Unit?

If you are a trained technician who knows the ins and outs of a transformer, you can definitely do this job yourself. However, if you are not, you better think twice before taking on the job. Ask yourself whether it is worth paying a trained technician to do the job correctly? Or you are willing to foot the bill for a new HVAC unit if you make a hash of things? The answer will lead you in the right direction. 

Conclusion

Time and again, electrical equipment malfunction. The good thing is that a malfunction does not mean you need to buy a new one. Today, you can simply replace the faulty or the bad component and your machine will be as good as new. HVAC units are no different. You can replace the part that has fried or melted, and once that is done, it will start functioning as normally as before. A few things to keep in mind are – take good care of your HVAC unit through regular maintenance and try to refrain from carrying out any repairs yourself. 

If you are not careful, you may do more harm to the unit and maybe even get hurt or injured. There are people who are trained to care of such things, and they even have the necessary tools and replacement parts to complete the job quickly. Book an appointment with your local HVAC company if your unit is behaving abnormally. They are the most trusted people to take care of things immediately.

Frequently Asked Questions

If your transformer is bad, you will have a tripped circuit breaker. It tips to prevent a voltage surge which can fry various parts inside the HVAC system resulting in a major breakdown of the equipment.

Similarly, a transformer with clear burn marks or a bulged exterior is also a sign of a bad transformer.

You may face any of the following issues when the furnace transformer goes bad:

1. There is a loud humming sound coming from the unit with a dramatic increase in vibrations.

2. The circuit breaker trips frequently.

3. The unit stops working correctly even with an adequate power supply.

You can test an HVAC transformer using a multimeter. First, switch the multimeter to “Ohms.” Next, disconnect the electricity from the transformer. Now attach the multimeter and check the ohms reading for the primary and secondary windings. Ideally, the reading should be between 1 to 10 ohms. If it is higher, the HVAC transformer is bad.

There are several reasons that could lead to the HVAC transformer failure. Some common causes are corrosion, wear and tear, overloading, power surge, fluctuations, moisture, strong winds, rain, and lightning strikes.

Mostly, the transformer will burn when the load on it becomes too great. Sometimes sunlight on wires rots the insulation and shorts them. The other probable reasons are loose wiring, worn-out parts, and the accumulation of dust on the transformer.

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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.
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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!!!
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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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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.
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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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Albert Rodriguez did a great job!!!
Would highly recommend him!!!!
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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
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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.
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Dana Dussalt was awesome & very patient & courteous by ensuring our AC was functioning properly & explained in detail the issue that he resolved.
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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.
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Niko Garza completed a detailed diagnostic & flush of my home AC. Very professional and courteous. I highly recommend Aztil & Niko
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Paul gross was wonderful.
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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 ☆☆☆☆☆
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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.
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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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Niko was fantastic... knowledgeable and professional... answered all my questions and did it with a smile... I would want to see him for all my service calls moving forward... thanks Niko!
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Jordan & Harold did a great job taking care of our system. Highly recommend them.
Response from the owner:Hi Janie, thank you for your kind words! We're so glad to hear that Jordan and Harold did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
The Aztil technician Dana was very professional, knowledgeable and courteous. He resolved my issue and made the visit seamless. .
Response from the owner:Hi Jeffrey, 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.
Lazaro is an excellent Tech. Courteous and Professional. If possible ask for him for all your HVAC issues.
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Dana was great. He was very knowledgeable. Did nice work Easy to understand. Highly recommended
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Jorge and Dave we’re extremely professional. The AC installation was done quickly and meticulously. I can’t recommend them enough!

I also want to give a shout out to Paul Gross. He was my initial contact with Aztil. He explained all my options to me and suggested the best unit for my home. Paul was able to get me a great price and I’m very grateful for his advice.
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Dana, my service tech did an amazing job to keep my AC up and running. He contacted me on his i, and was here in a flash.

He also updated me on the condition of the AC for the future, made some recommendations for me to consider.

Keep Dana on my service list and THANK YOU DANA!!!!
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Dana did a excellent job. He listened as to what was wrong as if he really cared. I would reccommend him to anyone. Very nice and respectable and he knew what he was doing.
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Niko was excellent. Very happy with his service. Explained everything and was very professional.

Yesterday no ac!! Yikes. Dana was the technician who did not leave our house until he discovered and fixed the problem. Believe me, he missed dinner and this was a Friday night. Couldn’t be happier. Dana was so professional and knowledgeable. So happy we bought from Aztil and have a service contract with them. If you ever think it’s not worth having the service contract in case of emergency, when you have no ac and it’s sweltering outside, you will be so happy you made a smart decision! Thank you Dana and Aztil.
Response from the owner:Hi E. R., 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.
Ramon was very thorough.
Response from the owner:Hi Michael, thank you for your kind words! We're so glad to hear that Ramon did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Rafael
Was very informative, polite, and to the point in explaining warranty information, and what parts was needed for my air conditioner.

I look forward yo his next visit in 6 months.
Keeps us up to date.
Response from the owner:Hi Erlene, thank you for your kind words! We're so glad to hear that Rafael did an excellent job and that you were pleased with the outcome. Thank you for being a valued customer.
Ramon did an excellent job in servicing my air conditioners. He also called the office to get the permit issue resolved. He informed me that Aztil was recently sold and he is enthusiastic about the new management. I also see an improvement in the communication in the past month.
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The service tech Ramon did an excellent job doing maintenance on my ac and fixed my plaster on top of the ac unit!! Highly recommend!!!!
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I scheduled a routine check up and Cody came to my home. He was so knowledgable and found issues with AC and fixed them on the spot. He also found a major issue on my roof and I immediately called the HOA. I will definitely be asking him to come back for my next check up

Excellent Customer service Kudos Cody !!
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I appreciate the online appointment system and the follow up communication until the Tech arrives. Dana, the technician on my job was terrific. He was very thorough and courteous, willing to answer all of my questions with clarity. The only thing that keeps me from awarding a 5 was the price. The service was very satisfying and Dana was exemplary.
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