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Important certifications for heating and cooling professionals

If you’re looking for air conditioner repair in Chicago Loop or anywhere else, you might be surprised, and perhaps a little frightened, to know that there are very few certification requirements for HVAC technicians in Illinois. What that means is that when you’re evaluating HVAC companies to decide which should be the one to service your home, you’ll run into many companies that have very little experience in the HVAC industry. And unless you’re an HVAC expert yourself, it may be hard to differentiate between the real players and the pretenders

Fortunately, there are some national certifications that indicate that an HVAC technician is qualified. For example, at Deljo Heating, Cooling & Plumbing, all of our technicians hold NATE certifications. So, to help make sure you know how to separate the wheat from the chaff when it comes to HVAC companies, here are a couple of certifications to look out for during your evaluation.

North American Technician Excellence (NATE) Certification

As the Advanced Technology Institute puts it, “The North American Technician Excellence certification is the gold standard for technicians.” The reason for this is that, to be awarded the NATE certification, you’re required to complete and pass exams designed by experts who know how to ask questions that will weed out any technicians that aren’t prepared. Generally, you’ll find that if your technician is NATE certified, he or she will keep their job longer and they’ll know how to develop a relationship with their customers.

EPA 608 Certification

This certification is designed to ensure that a technician is educated and skilled enough to work with equipment that contains refrigerant, such as a window air conditioner or heat pump. This is an important certification because refrigerant is a hazardous substance and you don’t want just anyone handling this dangerous chemical in your home when they’re conducting air conditioner repair in Chicago Loop. It’s worth noting that this certification is broken down into four different types related to the types of appliances the technician is certified to work with.

Carrier Factory Authorized Dealer

Depending on your scenario, if you’re shopping for air conditioner repair in Chicago Loop, you may actually want to consider replacing your air conditioner. If that’s the case, it’s helpful to work with heating and cooling professionals who are Carrier Factory Authorized Dealers because they can help select the equipment that is best suited to your unique needs.

Client Testimonials

Read the opinions of our satisfied customers.

5 stars

This was my first time as a Deljo customer, and I was very pleased. My technician, Giovanni, was very thorough and diligent. He serviced my furnace and identified a faulty sensor that was causing the unit to shut itself down. Deljo ordered the part, and Giovanni replaced it a few days later. Overall, the team at Deljo was great. The dispatcher kept me informed about Giovanni’s arrival time, and the supervisor assisted Giovanni when he was diagnosing the problem with the furnace. I highly recommend Deljo.

Paul D. 10/15/2026

5 stars

I’ve used Deljo for over 10 years now and they always do a good job. Izzy was the technician for this visit and he did an excellent job with my winter maintenance on my multiple units in the household. He also addressed an issue while cleaning the furnace blower wheel. His communication was clear and concise with what he planned to do to address the issue quickly. He was confident and I had 0 concerns or questions. Great job Izzy!

Jeff S. 10/14/2026

5 stars

Paul was great! Arrived on time and completed maintenance on my humidifier, tankless water heater, and two furnaces. All work was performed under my Gold Star maintenance program, so all maintenance charges were covered. Paul did provide a few proposals for additional services on furnace & tankless water heater, but those were emailed to me for further consideration. Paul was friendly, knowledgeable, and answered all my questions.

Jack N. 10/12/2026

5 stars

Gabe did an excellent job with our annual service visit. He arrived in the early part of our service window, was friendly and knowledgeable, and got the work done in a very reasonable amount of time. I have great confidence in Deljo, and am a long-time customer.

Ruth C. 10/9/2026

5 stars

I’ve been using Deljo for 20 years for HVAC but now venture into enlisting their plumbing services. Bashar was very courteous, efficient & informative, and I’d definitely request him again for the next plumbing job. Great experience!

Christopher R. 10/2/2026

5 stars

Working with Deljo is always a good experience, and today’s appointment with Izzy was no different. He was able to come early which actually worked better with our schedules, but called me ahead of time to make sure that was okay. He was friendly and knowledgeable when he explained the work he had done during his visit and our options for fixes. He was also able to schedule a quote appointment for us while he was still here. We would highly recommend working with Izzy and the Deljo team!

Lauren H.  9/25/2026

5 stars

Drew performed the seasonal maintenance on my AC. It needed some repairs and updates and he was able to fix everything at the same appointment. He also noticed issues with the hot water heater and we were able to get ahead of that, as well.

Emily W. 9/11/2026

5 stars

I would leave six out of five stars if I could! My technician Jorge went above and beyond on his service. There was buildup in the rental property’s toilet from the previous tenant. One maintenance person did a surface level job of cleaning but did not fully remove the obstruction. Jorge went above and beyond and came to a solution and even explained the perpetual problems older toilet models can cause. Moving forward with this insight, I can perform my own upkeep the previous tenant did not. Thank you kindly!

Kayla K.  9/15/2026

5 stars

We just had our new boiler installed by Jonathan and Carlos. First rate work! They arrived on time, removed the old boiler, installed the new unit, and explained the features. Both guys were pleasant. Bring on the cold this winter! We are ready thanks to the team from Deljo.

Edward B.  6/26/2026

5 stars

Deljo’s heating and cooling team was awesome to work with. As a first-time homeowner, I really appreciated how clearly they explained everything and answered all my questions. From the quote to the install and follow-up, the service was top-notch. Highly recommend!

Lindsey A. Chicago, IL

5 stars

Matt did an amazing job. He serviced our home and our rental property. He gave us options to help our systems run more efficiently. He also told us about Deljo’s new plumbing inspection which was very affordable. He is great!

Jordan R. Chicago, IL

5 stars

We had a problem with our Humidifier and called Deljo. Jesus came out to help and was amazing. He was extremely knowledgeable, detail oriented, and super courteous. Amazing customer experience!

Jeff C. Chicago, IL

5 stars

Jordan and Jesus were extremely helpful and knowledgeable! We would 100% work with them and have them back. They were both very professional and efficiently fixed our heating system.

Emily L. Chicago, IL

5 stars

Shout out to Ernesto for coming out and servicing our furnace and air con. Deljo provides a great service and glad to trust them with our HVAC for our small business.

Lauren H. Chicago, IL

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