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With over 30 years of combined experience in heating and cooling systems, Design Flow Heating and Cooling, LLC knows how important it is to have a go-to HVAC company you can trust – and we are that company!

The reliable, professional, and knowledgeable team at Design Flow is committed to customer satisfaction and finding solutions that meet your needs.

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“I’ve been using Design Flow for about 7 years now and they are a fantastic company. Sammy was my tech today, he was very courteous and extremely knowledgeable. If you contact Design Flow for assistance you can be confident that the job will be done right. Would 100% recommend them.”
- Cory D.

“Needed some maintenance done on our ductless air unit, and our technician Sam was super friendly, knowledgeable and honest. Great service and reasonable price. Thank you!”

- Wendy P.

Photo of happy family after AC repair service from Design Flow Heating & Cooling. An Eldersburg, MD, HVAC company.


Don’t wait until you’re facing an HVAC emergency to work with a professional HVAC technician. Here are a few reasons to rely on us for HVAC maintenance:

Extend the longevity of your system

Avoid breakdowns and the need for costly repairs

Make sure your system is operating efficiently

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WaterFurnace GEOPRO Master Dealer

No matter what climate you live in, the temperature throughout the year varies. For some climates that means blazing summers that cool to frigid winters. What many people don’t realize is that the temperature below ground (regardless of climate or season) stays fairly consistent all year. While air temperatures can vary greatly from day to night or winter to summer, the temperature just a few feet below the earth’s surface stays an average 55°–70°F year-round.


Ductless ACs Improve Indoor Air Quality and Control Humidity

Your home’s Indoor air quality is often two to five times more polluted than outdoor air, according to the US Environmental Protection Agency (EPA). These pollutants contribute to many diseases as well as respiratory conditions like asthma and allergies.

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3 Health Benefits for Using Your AC While Sleeping

A major part of your health relies on getting a good night’s sleep. That’s why it’s not just important to run your air conditioner during the hot summer days. You also need to keep your home comfortably cool at night as well.

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4 Important Heat Pump Maintenance Tips

How often do you schedule a maintenance visit for the heat pump in your Eldersburg, MD home? Taking proper care of your heating, ventilation, and air conditioning (HVAC) system is the best way to ensure it will function efficiently and reach its full-service life potential.

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At Design Flow Heating & Cooling, we realize everybody’s financial situation is unique. That’s why we offer convenient options for new system installation and repair services. To find out what you qualify for, all you need to do is click the apply now button below.

Happy couple enjoying their home's indoor air quality, thanks to a visit from Design Flow Heating & Cooling.


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At Design Flow Heating & Cooling, we embrace the principles that lead to success. As a Bryant dealer, we understand the importance of unwavering dedication to delivering quality products and service. Our commitment to customer satisfaction and our unwavering pursuit of excellence in performance set us apart. Join us and experience the Design Flow Heating & Cooling difference firsthand!

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To get the best performance from your system, you want a contractor who’ll correctly size and install your outdoor unit and indoor units. This is where a Diamond Contractor’s specialized training comes in. The difference between an okay and fantastic install typically comes down to your contractor’s knowledge of the technology and experience with ductless installations.

Design Flow Heating & Cooling customers taking family photo with son, after using one of our special HVAC discounts in Eldersburg, MD.


Discover extraordinary value in our special deals! Move quickly to enjoy incredible savings and exclusive rewards.


Are you looking for an exciting new career opportunity? Become a part of the Design Flow Heating & Cooling team today! We’re currently hiring and are looking for talented, and motivated individuals to join our team.