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Honesty and Integrity from the Beginning

In 1972, Mike Hendricks, Sr., set out to create his own business. Trained as an aeronautical engineer, Mike specialized in designing equipment involving airflow, pressures, vacuums and electronic controls. That experience with complex airflow systems transferred easily to the HVAC industry. Mike wanted to create a straightforward, honest business that would succeed on the basis of his own skills and integrity. Most of his early customers were friends and colleagues. In 1973, as his customer list grew, he left the corporate world to devote his full attention to the endeavor.

In late 1973, he hired his first employee, Richard Dean, who was working his way through college at the University of Maryland. Over the next few years, Richard received his degree in information systems management, and they formed the partnership that is Environmental Systems Associates.

What Makes ESA Stand Out?

Dedication to things like quality and integrity is a big part of why ESA has succeeded in this business for more than 45 years. With your continued support, we hope to continue as your HVAC comfort provider for many more!

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Our policy is to offer honest products with added value—consumer information and education to help you, our customer, make the best decisions regarding your heating and cooling needs.


Businesses that last treat their staff like family, giving them everything they need to succeed. There are many long-term employees of ESA with 15, 20 years of experience or more who have stayed with us, helping the business grow.

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Commitment to Quality

Though Mike Sr. retired in 2012, our business philosophy remains the same as it was in 1972. We continue to pride ourselves on our customer service, product knowledge and application of new technologies to indoor environment and energy-efficient solutions.

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Contact Your Comfort Associates Today

Need a few details about one of our services or partnered brands? Give us a call at (410) 381-7991 for questions, concerns and anything in between. We respond to emails within one to two business days.

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Our Community Involvement – Making Howard County Better for All

We are grateful for the support the community has shown ESA over the years. In turn, we are committed to working toward making Howard County a better place for us all. We work through ACCA and The Arc of Howard County to manage an “adopt a group home” project that provides group homes with low-cost, quality heating and air conditioning service and equipment.

We also help sponsor other community causes such as the Kappa Phi Lambda Annual Martin Luther King, Jr., Day Breakfast; The First Tee of Howard County; Rebuilding Howard Together; Leadership Howard County; Howard County Community Foundation; community concerts; and sports activities.


A new career in a stable, growing industry is closer than you think. ESA and our team of comfort professionals is always looking for talented individuals to help out as technicians, installers and more. Get the details on open positions below.

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Our Happy Customers

Don’t just take our word for it! Discover what others are saying. Dive into reviews now and make confident choices based on real experiences.

Certifications and Awards

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