Top-of-the-Line HVAC Care!

Choose us for your HVAC needs—where quality meets reliability. Let’s get started!

Driven by Excellence in HVAC Service

Our team provides reliable and efficient HVAC services tailored to both residential and commercial needs. With 20 years of experience, we ensure each client receives the best possible solution. Trust us to elevate your environment.

Working Hours
  • Mon - Sat: 7:00 AM - 5:00 PM
  • Sun: Closed

Reliable and Efficient HVAC Services in Walnut Creek, CA

Facing HVAC problems often means unexpected disruptions and stress in your daily life. The inconvenience of a malfunctioning system can disrupt your comfort at home or productivity at work. When you need reliable solutions, ATC Mechanical is here to help in Walnut Creek, CA. Led by Stiliyan Simov, our team brings two decades of expertise to your doorstep, offering competitive pricing and top-tier service as a California-licensed contractor. Experience the comfort and relief that comes with professional HVAC services. Let us turn your HVAC troubles into comfort and efficiency with our comprehensive solutions.


13 Years of Delivering Top-Notch HVAC Solutions

Selecting ATC Mechanical means choosing reliability and efficiency at competitive prices. Founded over 13 years ago, we continue to deliver top-notch HVAC services tailored for every client, including:

  • HVAC Installation Services
  • HVAC Repair Services
  • HVAC Preventative Maintenance
  • HVAC Replacement/Upgrades
Explore Our Services

Find the Perfect HVAC Solutions to Meet Your Needs

HVAC Installation

Experience the difference with our HVAC installation services. Our comprehensive approach includes mounting indoor air handling units, installing outdoor condenser units, and ensuring all components like refrigerant lines and electrical connections are perfectly integrated for optimal operation.

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HVAC Repairs

Our HVAC repair services cover a wide range of needs from ductless systems to A/C and furnace repairs. Our team is skilled at identifying and fixing leaks, cleaning evaporator coils, and ensuring your system runs smoothly without hazards, enhancing efficiency and cooling capacity.

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HVAC Preventative Maintenance

Through our HVAC preventative maintenance services, we focus on cleaning and servicing key components like filters, coils, and fans. Regular inspections allow us to catch and address small issues before they become significant, minimizing the risk of unexpected breakdowns and extending the lifespan of your HVAC system.

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Upgrade Replacement

Choose our HVAC replacement services for upgrading your existing system. Whether you need a new furnace, air conditioner, or ductless mini-split system, we ensure you get the most suitable and updated HVAC system to meet your needs and enhance your environment efficiently.

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Experience Optimal Comfort

Premium HVAC Services at Fair Prices

Enhance your space with premier HVAC services in Walnut Creek, CA. Experience the difference with ATC Mechanical. Call us today!

Choose ATC Mechanical and expect nothing but our best. Our seasoned team guarantees efficient installations and speedy repairs, all at competitive prices. Don’t wait—reach out now and take the first step towards optimal comfort and reliability in your home or business.

Benefit From Our HVAC Expertise Now!

Book your HVAC service today and stay comfortable year-round. Act now!

Reaching Every Corner

Discover Our Service Areas

Find out how we bring our unmatched expertise to Walnut Creek, CA, and the surrounding areas.

Areas We Serve

Walnut Creek, CA
Concord, CA
Pleasant Hill, CA
Alamo, CA
Lafayette, CA
San Francisco, CA
Martinez, CA
Orinda, CA

See What Our Customers Have to Say!


Cvetelina Dobreva

ATC Mechanical helped me with heating repair. Special thanks to Stiliyan for his professional and quick work. I definitely recommend this company.

Google Review


Artour K

Installation of Samsung mini split with heat pump in Concord, CA.
I took quotes from 3 other companies before I signed a contract with ATC Mechanical. Smaller company that managed to give me a better price, without feeding me the usual corporate “greed”-flation stories.
Quick, neat and professional installation.
Will do business with with this company again!

Google Review


Natalie Torres

We are currently undergoing a major addition/renovation project at our home and needed to replace and upgrade our current HVAC system to a larger more efficient system, enlarging the existing ducts and a larger unit. ATC Mechanical was recommended to us by our general contractor, and we are so pleased. From the initial visit for an estimate price to the day of installation, Stiliyan and his team were professional, extremely knowledgeable, friendly, on time and left the work area clean and tidy. We would highly recommend ATC Mechanical to anyone for their HVAC needs. Thank you Stiliyan it was a pleasure working with you and your team.

Google Review


Alan Lewis

We needed to retrofit a heat pump in an awkward, barely suitable space in a remodeled older house. Stiliyan measured meticulously to make sure we could do it, then totally nailed the installation, and had the whole thing done in a couple of days. He and his crew were totally professional and a pleasure to work with.

Google Review


Farzaneh Pour Ansari

He is Skilled, professional. Honest, and on time. We are grateful finding him. Good people know good people. He also referred us to a professional and honest plumber. Thank you!

Google Review


Fari Ansari

I am so happy with the service I have received, he is so honest, he has high integrity, very professional and caring.
He was on time, fixed the problem, very affordable and had a follow up appointment make sure the heater is working well.
I highly recommend him and kid company

Google Review


Ben Chirko

Stiliyan from ATC Mechanical was amazing. As someone who works in the real estate industry and deals with property issues frequently I would highly recommend Stiliyan for your HVAC needs. I had a lingering air flow issue where my two back bedrooms didn’t get proper air flow from the furnace. The system was 1 year old and the original installer gave me no option but to rip out the duct work and start over costing thousands of dollars and damaging my brand new ADU. Stiliyan came by and recommended a very simple solution to improve air flow which I had never heard of. I really didn’t think it would work, but it completely solved the air flow issue. I was truly amazed and have been much cooler this summer! Thank you to Stiliyan and the ATC Mechanical team for a creative solution which saved me thousand of dollars!

Google Review


Maile Williams

I had 2 other well known AC and heating companies come out to find out why my moms AC was not working. It took them hours to look at the AC and try and figure it out. One suggested I needed a new AC, the other said I needed a new compressor. I had ATC Mechanical come out and in 30 minutes the unit was working and they had diagnosed the problem. I highly , highly recommend them and will be referring all my friends to them. They’re honest and efficient!

Google Review

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