Having an HVAC malfunction during the summer can be really uncomfortable. If you notice that your air conditioner is running but has stopped cooling the air, you should start investigating the possible causes. This symptom can be attributed to a list of issues that may or may not require professional attention.
Here is what to start looking for and what to do when your unit stops cooling.
Update 4/6/26: Zach Sperling is such a pleasant and knowledgeable technician that I recommend him highly. Thomas Heating has been a wonderful company to work with in my maintenance plan. If you are looking for a reputable company, look no more.
This company is so responsive that I love them. They respond immediately, and I trust them to tell me what needs to be done. I haven’t been steered wrong yet. They are genuinely nice to work with and honest. I use their maintenance program which I highly recommend.
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work good but got at least 6 messages from them very annoying
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Nick was great! He came right out and was able to solve the problem fairly easily. He communicated well and helped us prevent a future problem as well.
Response from the owner:Thank you for the review, Philip! We are happy to hear you had a pleasant experience working with us.
Response from the owner:Thank you, Pat, for your kind words about Giovanni; we appreciate your feedback and are glad to hear that he made a positive impression.
They have never failed to fix my hvac problems. These folks are top tier.
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Giovanni was very professional, helpful, patient and helped me figure out the issue, if it was covered under warranty, and next steps. Great overall experience and much appreciated.
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Always professional and thorough whenever they service our home. We have used Thomas Hoffmann Air Conditioning & Heating multiple times since we moved into our home and will continue to use them in the future.
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0 stars if I could. Bought a faulty (not to mention overpriced) surface igniter, called back five minutes later after installing, of course they didn’t stand behind their part. Go to Grainger instead. Same (working) part, half the price.
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From the phone to the completion of the job everyone is so polite and informative. I had Giovani as our representative and he was very informative and professional, and knew exactly what the problem was. Thanks so much.
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My furnace was not working. A very nice gentleman came out this morning and fixed the problem and now I have much needed heat. He was very professional and courteous. I will definitely be using them again when the need arises.
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I will always call Hoffmans for my air and heat needs. They were out to my daughters house that day and fixed it. It was right before the weekend storm with below zero temps the next day. They saved my daughter and grandbabies. I could never thank them more.
Response from the owner:We are so happy to hear that we could help! Thank you for the kind review.
Snow and drifting snow covered intake and out take vents causing the furnace emergency to shut off furnace. Cleaned off the driftibg/ snow off roof and vents furnace works perfect now. Thank you and great job Nick.
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5 stars! Nick was here to fix my heater within 2 hours of my call. He explained the problem to me thoroughly and got the job done quickly & professionally. Thank you so much!
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Extremely thorough and educational. They do a wonderful job of explaining everything and making sure I was comfortable knowing how the systems worked in my house!
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I noticed a strange noise that I was concerned was linked to my furnace. I called Thomas Hoffman Heating & Cooling and Nick came right out. He was very thorough checking all components. Thankfully all checked out for us this visit. Definitely recommend Thomas Hoffman Heating & Cooling!
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Thomas Hoffman is a wonderful company to work with. Techs are knowledgeable, personable & efficient.
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Got a quote over the phone. Everything was explained thoroughly. Dakota, my technician arrived and on time, was very professional and knowledgeable. He didn’t try to upsell or change anything. He did a great job. We can already tell the difference since the ducts and vents were cleaned. Would recommend an use Hoffman again in the future.
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The technician, Ryan, was knowledgeable and helpful in identifying the issue with our mini split AC unit. They are the second company we called after issues with the first and will be using Hoffmann again.
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woke up to a very cold house, called Thomas Hoffmann, they were able to come out a couple of hours later and get the issue resolved. Always trust them, they have always been quick to respond and get either the heating or ac issue fixed that day. Also a great price!!!! give them 10 stars if i could, Thank You JS
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The technician Giovanni was excellent and on time very professional and efficient and knowledgeable of the project at hand ,gave great advice but most of all did great work đź‘Ź thank you .
Response from the owner:We are so happy to hear you had a great experience, Sam! Thank you for the review, and thank you for your business.
Create the Proper Conditions for a Diagnosis
Before you can identify the possible causes of your HVAC malfunction, make sure you create good conditions for testing it.
First of all, close all your windows to prevent hot air from coming inside.
Check the current room temperature and set your thermostat to a cooler value, it may simply not be set correctly.
If you are using other air processing appliances like humidifiers or air purifiers, turn them off.
Check the vents and make sure they are not obstructed.
Once you have created these conditions, it’s time to find the culprit through elimination. It’s possible that after taking these steps, you may notice that your system is actually working correctly. If not, here is a list of the most common causes for an HVAC unit that is running but not cooling. Get in touch with an HVAC technician who can help identify and resolve any issues with your air conditioner.
Refrigerant Leaks
Refrigerant is the substance used in air conditioning units and refrigerators to cool the air or fluid that circulates through them. If your HVAC system has refrigerant leaks, it will simply not be able to cool the air, but it will still circulate it. Some units can self-diagnose low refrigerant, but without such a feature, only an HVAC professional can measure the level of the refrigerant.
Clogged HVAC Interior
Air not cooling can be a sign of improper maintenance of the HVAC unit. Follow the manufacturer’s instructions for routine maintenance and clean the air filters, coil, condenser, evaporator, etc. Clear any debris or vegetation around the outdoor unit and make sure the unit is not flooded with water.
Insufficient Airflow
Another cause for the HVAC not cooling down your house is that the cool air never gets to the interior. Fortunately, this means that the unit itself works perfectly, but you need to investigate the airflow before the problem worsens. Check the cold air returns to see if there is any suction (try using a paper tissue to check the movement of the air). All the vents in your house should let the air flow properly.
Thermostat Malfunction
Your HVAC unit may be working perfectly, but the thermostat is having some sort of issue. Make sure it works properly by checking the display if it’s blank you might want to try replacing the batteries or calling an HVAC expert to check the wiring.
Electrical Malfunction
Most issues that HVAC repair teams deal with are caused by electrical malfunctions. If you notice that your HVAC unit has stopped cooling the air, check the electric panel to see if any of the breakers were tripped. They should be labeled for easy identification. Try flipping them in the off position and see if that solves your problem.
Frequently Asked Questions
This could be due to a variety of issues such as low refrigerant levels, clogged filters, or electrical problems. It’s best to have a professional HVAC technician diagnose and resolve these issues, as they have the tools and expertise to handle refrigerants and electrical systems safely.
Often, this indicates that something is preventing the system from functioning efficiently. Possible reasons include a malfunctioning thermostat, blocked vents, or internal obstructions. A professional can conduct a thorough check to identify and fix the underlying problem.
It’s advisable to ensure that the thermostat is set correctly and that there are no obvious blockages affecting air flow. Beyond these basic checks, contacting a qualified HVAC professional is the safest way to handle issues like refrigerant leaks or system recalibration.
Handling HVAC issues involves dealing with complex components that might require handling hazardous materials or electrical systems. Therefore, while routine maintenance like cleaning accessible filters and ensuring clear surroundings can generally be done safely, any deeper issues should be addressed by professionals.
Common reasons can include issues with the thermostat settings, blockages in the air circulation paths, or mechanical failures within the unit. An HVAC technician can offer the best solutions after a professional assessment, ensuring that any repairs or adjustments are done safely and effectively.
If you notice that your air conditioner is running but not cooling your home, give our team a call today and we’ll get to the bottom of your issue!
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At Thomas Hoffmann Air Conditioning & Heating, we pride ourselves on being a locally owned and operated HVAC company. With more than 30 years of experience and a master technician and mechanical engineer as our owner, we can replace, repair, and maintain your business or home’s HVAC system.
