About Us

Ground Loop Heating and Air Conditioning, is a third-generation family-owned heating and air conditioning business specializing in WaterFurnace geothermal systems. What started as a small sheet metal company in Maryland is now one of the most established geothermal companies in the entire country.

For over 30 years, our company has been designing and installing HVAC systems of all sizes for residential and light commercial applications. We are leaders in innovative technologies that keep families and businesses comfortable, all while saving money and preserving our resources for future generations. Our IGSHPA-certified installers strive for complete customer satisfaction on every job.

Many people in town still remember us as Dublin Sheet Metal, the company Al Cullum started in the basement of his Darlington home. He later became Dublin Heating and Air Conditioning, which he ran with his two sons Mike and Gary. Mike eventually went off to carve out his own path, and Ground Loop Heating and Air Conditioning was born. Today, he runs the business with his two sons, Jason and Scott.

At Ground Loop Heating and Air Conditioning, our entire team operates on the principles of honesty, integrity, and quality work delivery. We have installed thousands of geothermal systems in Maryland and the surrounding areas. Our A+ rating with the Better Business Bureau tells you we are a company you can trust.

We offer top-of-the-line geothermal products at competitive prices, thanks to our extensive industry, relationships, and longtime customer loyalty. We are familiar with the requirements of general contractors and will coordinate with project managers, architects, designers, site managers, and other sub-contractors to facilitate a smooth installation process.

We go above and beyond to ensure the installation process is minimally disruptive to your life—and we are always available to answer any questions you may have.

HVAC Services

Our experts can install, repair, and maintain every piece of HVAC equipment in your home, including heat pumps, boilers, air conditioners, gas furnaces, oil furnaces, and mini splits. When it comes to making your home or business comfortable and safe, Ground Loop Heating and Air Conditioning has the HVAC solution for you.

Meet the Team

Having a courteous and knowledgeable staff at Ground Loop Heating and Air Conditioning allows us to cater to exactly what our customers need. We offer great financing packages and work extra hard for complete customer satisfaction. We understand that geothermal and HVAC systems are significant investments and want to ensure you get the most value from them.

Michael Cullum, Company President

Mike is one of the most knowledgeable and highly respected members of the geothermal community. His reputation of quality combined with his 30 years of experience and dedication to the industry make him one of the top installers in the United States. Its because of Mikes hard work and dedication over the past 30 years, that he is now able to slow down and enjoy life. He works on an as needed basis and spend most of his time on his boat (the “Bay Loop”) trying to teach his grandsons about heating and air.

Jason Cullum, Vice President

Living all his life in a house with geothermal heating and cooling, working on loops, and helping his father with service as a kid, installing systems as a teenager during the summer, to sales, and management. Jason lives and breathes geothermal. He is now the company Vice President and spends most of his time growing the company and trying to bring more value to our customers. He understands all the advantages and exactly what can be expected from installing a geothermal heating and cooling system. His primary responsibility is to oversee the great people at Ground Loop Heating and Air Conditioning who run the day to day operations. Jason is currently the Vice President of the Maryland Geothermal Association and works with state and local legislature to further the industry through awareness and education.

Accreditations: IGSHPA-Certified Geothermal Inspector and IGSHPA-Certified Installer. He is a Waterfurnace Certified Ground Heat Exchanger Designer, Installer, and Service Technician. Jason is the Vice President of the Maryland Geothermal Association, and is a board member for the International Ground Source Heat Pump Association.

Ted Evans, Sales Manager

After 20 years of extensive field work in the HVAC industry, Ted assumed a sales and project management position at Ground Loop Heating and Air Conditioning. His knowledge and understanding of all heating and cooling methods allow him to truly understand and explain the benefits of geothermal systems. His main responsibilities are to meet with prospective customers to educate them on the benefits of geothermal heating and cooling, evaluate their specific situation, and identify which system will work best for their needs. Ted is extremely knowledgeable and has a very practical and laid-back approach to the sales process.

Joe Heaps, Lead Mechanic

Joe Heaps was Ground Loop Heating and Air Conditioning’s lead mechanic for installing new geothermal systems for over 25 years. He is known in the industry for his meticulous work and attention to detail. He is now Ground Loop's Field Supervisor and works with homeowners and our installers to coordinate and manage installations on site. Joe is extremely knowledgeable on exactly how to layout and install HVAC of all kinds and knows how to avoid the pitfalls and mistakes most beginners make.


Our installers may be the ones with whom you’re most familiar. These crews come to your home or job site and actually lay the loops in the ground and tie in the units. These are dedicated and professional individuals who get the job done and are available to answer on-site questions as needed.

If you’re considering investing in a geothermal system, trust your project to the experts at Ground Loop Heating and Air Conditioning. Give us a call at 410-836-1706 to learn more about how we can make your home more comfortable and energy-efficient than ever and to schedule your free estimate.

Ground Loop Heating and Air Conditioning provides geothermal air conditioning system installation and air conditioning system maintenance services to clients throughout Maryland, including Baltimore, Harford County, Anne Arundel County, Howard County, Baltimore County, Cecil County, Carroll County, Montgomery County, PG County, Kent County, and Queen Anne’s County.

Need HVAC Service?

Contact the experts at Ground Loop Heating and Air Conditioning.

Call us at 410-836-1706!