If your air conditioner keeps turning on and off every few minutes, it’s usually a sign that something isn’t working correctly.
This issue is commonly known as AC short cycling, and it can lead to higher energy bills, reduced comfort, and unnecessary wear on your HVAC system.
For homeowners in St. Louis, short cycling is especially frustrating during hot, humid summer days, when your air conditioner should be running steadily to keep your home comfortable.
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.
Response from the owner:Thank you for the kind review, Frank! We appreciate you and your business.
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.
Response from the owner:Thank you for the positive feedback! We're glad to hear that you were pleased with our prompt and friendly service. We look forward to assisting you again in the future!
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.
Response from the owner:Thanks for the great review, Scott! We appreciate your support.
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!
Response from the owner:Thank you for the kind review, Jennifer! Glad we could help.
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!
Response from the owner:Thanks for the great review, Matthew! We appreciate your support.
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!
Response from the owner:Thank you so much for the kind review, Abby! We appreciate your business and look forward to servicing you in the future.
Thomas Hoffman is a wonderful company to work with. Techs are knowledgeable, personable & efficient.
Response from the owner:Thank you, Christine, for your kind words about our team; we appreciate your feedback and are glad to hear you had a positive experience!
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.
Response from the owner:Happy to hear you had a pleasant experience using Thomas Hoffmann!
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.
Response from the owner:We are so happy to hear your experience with Thomas Hoffmann was pleasant. Thank you for your kind review, & we look forward to working with you in the future!
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
Response from the owner:Thank you for the kind review, Jim. We are happy to hear that you had a positive experience working with Thomas Hoffmann!
Response from the owner:Thank you, Hank, for your wonderful feedback; we're glad you enjoyed the fast, friendly, and professional service, and we'll be sure to keep up the great work!
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 👏 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.
Your service technician was very professional and knowledgeable. And did not appear to try to give me bogus information. I truly appreciate his honesty because several other companies did not appear to be honest, obviously wasn’t honest, my gut feeling told me they were not honest and tried to get me to spend $10,000 for a problem that was much simpler to fix. I look forward to you servicing all my properties, and possibly those of the rest of my family.
Response from the owner:Thank you so much for the kind words and great review! We appreciate your support.
Very prompt, communication was great, and the workers were very polite. I highly recommend them!
Response from the owner:Thank you, Lianne! We're glad to hear that you had a positive experience with our team and appreciate your high recommendation.
Water heater repaired, appointment done the same day, effective, courteous
Response from the owner:Thank you, Leticia! We appreciate your kind words and are glad to hear that the water heater was repaired promptly and effectively. Your satisfaction means a lot to us!
The service tech Giovanni did a fantastic job. Our gas fireplace is working like new again so we’re ready for the cold weather!
Response from the owner:Thank you, Mr, for your fantastic review! We're glad to hear Giovanni provided you with excellent service and professionalism. Your recommendation means a lot to us!
⭐️⭐️⭐️⭐️⭐️ If I could give 10 stars, I absolutely would.
Last night our furnace went out unexpectedly, and with three kids in the house, the temperature dropped fast. Giovanni went above and beyond in every way possible. Instead of charging me a late-night service fee, he simply asked, “Are you decently handy?” and offered to walk me through some troubleshooting steps to get our heat back on so my children wouldn’t have to sleep in the cold.
Not only did he guide me through the process, he even FaceTimed me and showed me exactly what to take apart, how to put it back together, and what signals to watch for. It felt like having a real technician standing right next to me the entire time. Thanks to him, our heat was restored within minutes.
In a world where true customer service is hard to come by, Giovanni is a rare find. It is a guaranteed fact that any future repairs, maintenance, and the new heater/AC system we’ll be needing this coming summer/fall will absolutely be done through him. His honesty, kindness, and expertise have earned our business for life.
Highly, highly recommend.
Response from the owner:Thank you, Jeff, for sharing your experience! We're so glad to hear Giovanni was able to help you and your family during that tough situation. Your recommendation means a lot to us, and we appreciate your trust in our services for the future!
My neighbor referred these guys to me when had water heater problem. Previous company told me I needed to replace it. Tom’s technician fixed it for less than $200. This was over 2 years ago and have been using their service ever since. They are very trustworthy.
Response from the owner:Thank you, Mary, for sharing your experience and for trusting us with your water heater issue; we're glad our technician could help and that you've continued to rely on our services!
Speedy response and service. Knowledgeable professional. Kind, courteous, friendly but professional.
Response from the owner:Thanks for the great review! We appreciate your business and look forward to working with you in the future.
What is Air Conditioner Short Cycling?
Short cycling happens when your air conditioner:
Turns on
Runs briefly
Shuts off quickly
Then turns back on again shortly after
Instead of completing a full cooling cycle, the system repeatedly starts and stops. Normally, an air conditioner should run for 10–15 minutes per cycle, or longer, depending on outdoor temperatures and cooling demand. When cycles become extremely short, the system never fully cools your home or properly removes humidity.
Why Short Cycling Is a Problem
When your AC keeps turning on and off, it can cause several issues:
One of the most common causes of AC problems is a clogged air filter. When the filter becomes dirty, airflow through the system is restricted. This can cause the evaporator coil to become too cold, disrupting normal operation. Symptoms may include:
AC turning off quickly
Reduced airflow from vents
Ice forming on the indoor coil
Changing the air filter every 1–3 months can help prevent this problem.
If your AC coil freezes, the system may begin short-cycling. Frozen coils often occur due to:
Dirty air filters
Blocked vents
Low refrigerant levels
Poor airflow
When the coil freezes, the AC may shut down to prevent damage. If you notice ice on refrigerant lines or the indoor unit, it’s time to schedule AC repair.
Many homeowners are surprised to learn that an oversized AC can cause short cycling. A system that is too large cools the home too quickly and shuts off before completing a full cycle. This leads to:
Frequent on-and-off cycles
Poor humidity removal
Uneven temperatures
Oversized systems are sometimes installed when proper load calculations are skipped.
Electrical components help regulate when your AC starts and stops. If these components begin to fail, the system may cycle erratically. Possible electrical issues include:
Failing capacitors
Loose wiring connections
Control board problems
Contactor issues
Electrical repairs should always be handled by a licensed HVAC technician.
5. Blocked or Closed Vents
Your HVAC system relies on balanced airflow throughout your home. If too many vents are closed or blocked, pressure builds up in the duct system and can interfere with proper system operation. This can cause:
Short cycling
Reduced airflow
Uneven cooling
Make sure supply vents and return vents remain open and unobstructed.
Signs You Should Call for Air Conditioner Repair
Short cycling should never be ignored. You should schedule AC repair if:
Addressing the issue early can prevent more expensive repairs later.
How Regular AC Maintenance Prevents Short Cycling
Many causes of short cycling can be prevented with regular HVAC maintenance. A professional AC tune-up typically includes:
Checking refrigerant levels
Cleaning condenser coils
Inspecting electrical components
Checking airflow
Testing thermostat operation
Inspecting the evaporator coil
Regular maintenance helps your system run efficiently and reliably during the St. Louis summer.
Air Conditioning Repair in St. Louis
If your air conditioner keeps turning on and off, a professional inspection can identify the cause and restore proper operation. Thomas Hoffmann Air Conditioning & Heating LLC provides trusted AC repair services for homeowners throughout the St. Louis metro area. Call today to schedule AC repair:(314) 471-7625
24/7 Service Call Now
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.
