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Until You Are

The weather is always comfortable inside your home, thanks to Design-Air Heating and Air Conditioning.

happy husband and wife in kitchen living in the comfort of their home sullivan illinois

Certified Heating & Air Conditioning Technicians
Sullivan Illinois

Since 1977, Design-Air Heating & Air Conditioning has been the leading expert in HVAC for Sullivan, IL and the surrounding areas. We handle everything from AC maintenance and repair to furnace replacement and diagnosis services. All our trained technicians are NATE-certified, making us knowledgeable on all types of HVAC servicing for name-brand makes and models. Whether your air conditioner needs a filter replacement or your home’s air quality needs to be tested, there’s nothing our HVAC team can’t do.

As a family-owned and operated business, we care about the safety and comfort of your home. Contact our shop for a free estimate and consultation from a Design-Air Heating & Air Conditioning technician.

Air Conditioning Services
Sullivan Illinois

When your air conditioning unit stops working or starts blowing warm air into your home, Design-Air Heating & Air Conditioning is here to provide expert AC repair, maintenance, and installation services to restore your home. All our technicians are NATE-certified and have decades of experience working on all AC makes and models from name-brand manufacturers. Whether you need routine maintenance service or your current air conditioner can no longer be repaired, our team will work to find you the most affordable option to restore the cooling needs of your home in Sullivan, IL.

Get a free estimate on all of our AC replacement services and schedule an emergency service when you call 217.429.1105.

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Furnace Services
Sullivan Illinois

When winter arrives in Sullivan, IL, it’s important to have a working furnace that can keep your home comfortable all season long. If you notice the pilot light is out, or your furnace is blowing cool air, it may be time to call our professionals at Design-Air Heating & Air Conditioning. Our family-owned business specializes in residential furnace repair, maintenance, and installation services from all name-brand makes and models. One of our NATE-certified technicians will start with a thorough diagnosis to find the cause of your furnace failure and provide reliable repairs to restore heat to your home.

Don’t wait until your home starts to freeze; contact our experienced team for a furnace repair or replacement service.

Indoor Air Treatment
Sullivan Illinois

As modern structures become more secure, creating quality indoor air filtration in homes and businesses is more important than ever. With over 45 years of industry experience, Design-Air Heating & Air Conditioning understands how indoor air quality affects our way of life. Clogged air filters, dusty air ducts, and pet dander piling in the corners of your living spaces can cause anything from headaches and stuffy noses to serious respiratory issues. Thankfully, our NATE-certified technicians offer several indoor air treatment options for residential and commercial properties in Sullivan, IL.

Get rid of harmful allergens while creating clean, breathable airways when you invest in an air purifier, humidifier, or electric air cleaner from our shop.

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Quality Service for the Comfort of Your Home

Whether you need services for your air conditioning, heating, air-quality, or other HVAC services, Design-Air Heating & Air Conditioning is here to support you and take on any job.

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Geothermal Heating
Sullivan Illinois

Upgrade your home’s heating and cooling system with modern energy solutions from Design-Air Heating & Air Conditioning in Sullivan, IL. Since 1985, we have been the #1 choice for geothermal heat pump installation for homes and businesses throughout Central IL. We offer in-floor radiant heating systems, which are installed below your flooring and connected to your electric supply for instant heating to your home. Whether you’re looking to upgrade your property to a geothermal heating and cooling system or your current heat pump needs repair, our NATE-certified technicians are here to help.

Geothermal energy is eco-friendly and guaranteed to help you save money on your monthly utility bill. Learn more when you get in touch with our team today.

Commercial HVAC
Sullivan Illinois

If you own a business in Sullivan, IL, it’s essential to have your heating and cooling systems maintained year round for optimal performance. Design-Air Heating & Air Conditioning has over 45 years of HVAC repair, installation, and maintenance experience to provide high-quality services to your commercial systems. Whether your air conditioner is blowing warm air or your furnace won’t turn on, you need a team of experts to perform immediate restoration to keep your business running. Our NATE-certified technicians work on all commercial AC and furnace makes and models, so your business is never compromised.

For a free estimate on our system replacement services or to schedule an emergency repair, get in touch with our team at 217.429.1105.

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Ductless Split System
Sullivan Illinois

Design-Air Heating & Air Conditioning specializes in ductless split unit maintenance, repair, and installation for residential and commercial properties in Sullivan, IL. Ductless systems deliver comfort wherever it is needed, from homes and schools to corporate buildings and hotels. Our units are available in a range of shapes and sizes, and they may be installed indoors or outdoors, making them adaptable to your individual requirements. Our HVAC technicians have over 45 years of industry experience and can quickly diagnose the problem with your unit and provide rapid repairs that are within your budget. Schedule an appointment with our experts as soon as you’re ready to invest in a ductless system or notice a lack of efficiency from your current ductless unit. To provide our consumers with high-quality results, we offer free estimates and employ fully qualified and educated technicians on our team.

Our products are energy-efficient, cost-effective, and easy to install, and our specialists will be available to assist you from the day of installation through whatever repairs are required throughout your unit’s lifetime. You’ll have our support every step of the way.

New Construction Installation
Sullivan Illinois

When you want a business that produces exceptional outcomes for your new building installation, Design-Air Heating & Air Conditioning is an ideal choice. When you engage with our professionals in Sullivan, IL, whether you’re building a new home or a company, your satisfaction is always guaranteed. Allow us to design a space that is both beautiful and functional. You’ll need a location that is comfortable for everyone, so consult with our heating and air conditioning professionals who have years of experience. Put your trust in us, and you will reap the benefits of working with the best in the industry. Allow us to walk you through our process and consult with you on your next project’s vision. We can make your dream a reality if we work together. Once the high-quality HVAC equipment has been installed to fit your space and perform properly, our expert technicians will keep it in top shape by providing continuing maintenance services anytime you require professional examinations or repairs.

Whatever services you require, we can provide them to keep your building efficient, safe, comfortable, and welcoming to your guests.

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father, mother, and child having fun in home enjoying the comfortable temperatures decatur illinois
couple cozy in home

Why Choose Design-Air Heating & Air Conditioning?

Design-Air Heating & Air Conditioning has been the leading HVAC expert for over four decades. Since then, we have provided long-lasting repair, replacement, and maintenance services to homes and businesses throughout Sullivan, IL. Here are just a few reasons our customers continue to choose us for their air conditioning & furnace services.

  • Free Estimates on Replacements

  • In Business For 45+ Years

  • Carrier Authorized Dealer

  • Emergency HVAC Services

  • Family Owned & Operated Business

  • NATE Certified Technicians

  • In Business For 45+ Years

  • Free Estimates on Replacements

  • NATE Certified Technicians

  • Carrier Authorized Dealer

  • Emergency HVAC Services

  • Family Owned & Operated Business


Why Our Clients Choose Design-Air Heating & Air Conditioning

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Schedule Appointment

Monday thru Friday 7:30A – 4:00P To schedule non-emergency service or standard maintenance, please call 217.429.1105 or complete the form below:
Contact Information
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