Welcome to Markool Heating & Cooling. We proudly provide the highest quality of service and craftsmanship for each aspect of your project. Our depth of knowledge and experience solidify our belief that customer service stands as the highest priority. We eagerly look forward to working with you and making your vision a reality. Give us a call, text, or email today, and let us get started!
"Woke up this morning to my hvac leaking and contacted Markool. I have never used them before and was in a pinch. They fit me right in this morning and were out at my house within 2 hours. The tech stepped in the door and placed covers for his shoes so he did not track in any dirt which was impressive! The tech was very professional and super friendly. Problem was diagnosed and FIXED within an hour. The price was extremely reasonable to the point I was shocked in a good way (expecting a higher price). Anyways, I will most certainly be a returning customer. Thank you Markool Heating Cooling Plumbing."
Chase R on August 2024
Welcome to Markool Heating & Cooling. We proudly provide the highest quality of service and craftsmanship for each aspect of your project. Our depth of knowledge and experience solidify our belief that customer service stands as the highest priority. We eagerly look forward to working with you and making your vision a reality. Give us a call, text, or email today, and let us get started!
"Woke up this morning to my hvac leaking and contacted Markool. I have never used them before and was in a pinch. They fit me right in this morning and were out at my house within 2 hours. The tech stepped in the door and placed covers for his shoes so he did not track in any dirt which was impressive! The tech was very professional and super friendly. Problem was diagnosed and FIXED within an hour. The price was extremely reasonable to the point I was shocked in a good way (expecting a higher price). Anyways, I will most certainly be a returning customer. Thank you Markool Heating Cooling Plumbing."
Chase R on August 2024
Horizon Services (MD), LLC, is the regions largest and most well respected plumbing, heating and air conditioning company, with nearly 600 employees serving tens of thousands of homeowners throughout Delaware, Southeastern Pennsylvania, Southern New Jersey and Northeastern Maryland. After a quarter of a century in business, Horizon Services (MD), LLC, remains fully committed to setting the industry standard for customer service, installation and focusing on things that are important to busy homeowners.
"Good job"
maribel c on March 2025
Horizon Services (MD), LLC, is the regions largest and most well respected plumbing, heating and air conditioning company, with nearly 600 employees serving tens of thousands of homeowners throughout Delaware, Southeastern Pennsylvania, Southern New Jersey and Northeastern Maryland. After a quarter of a century in business, Horizon Services (MD), LLC, remains fully committed to setting the industry standard for customer service, installation and focusing on things that are important to busy homeowners.
"Good job"
maribel c on March 2025
Thank you for visiting FREEDOM GENERAL SERVICES, LLC. We are your locally owned and operated HVAC specialists based in Gambrills, MD. We service residential and commercial clients throughout MD. Contact us now for your free estimate--we look forward to working with you soon!
"The sump pump stopped working and flooded the entire basement that had just been converted to a full living space including kitchen, new bathroom, office, and bedroom. They had to completely redo it. Replacing the drywall throughout. Freedom General Services literally came to the rescue! Tearing out the damage and rebuilding the new. I am thrilled! And the painting sub-contractors were WOMAN!! Inclusivity is the name of their game!"
Pauline H on October 2024
Thank you for visiting FREEDOM GENERAL SERVICES, LLC. We are your locally owned and operated HVAC specialists based in Gambrills, MD. We service residential and commercial clients throughout MD. Contact us now for your free estimate--we look forward to working with you soon!
"The sump pump stopped working and flooded the entire basement that had just been converted to a full living space including kitchen, new bathroom, office, and bedroom. They had to completely redo it. Replacing the drywall throughout. Freedom General Services literally came to the rescue! Tearing out the damage and rebuilding the new. I am thrilled! And the painting sub-contractors were WOMAN!! Inclusivity is the name of their game!"
Pauline H on October 2024
It is our mission, to provide excellent workmanship and complete customer satisfaction, from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety and quality, regardless of how large or small the job.
"They took the time to diagnose the issue and then clearly explained what was going on."
Richard I on January 2025
It is our mission, to provide excellent workmanship and complete customer satisfaction, from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety and quality, regardless of how large or small the job.
"They took the time to diagnose the issue and then clearly explained what was going on."
Richard I on January 2025
Beltway Air Conditioning & Heating , LLC, is a family owned and operated business located in Hanover. We offer everything you need to heat, cool, and improve your indoor air quality in every corner of your home. Our high quality work with a smile is what keeps our customers satisfied. We make sure that we pay close attention to the details and take pride in delivering professional results to you at competitive rates.
"New Beltway is the best choice for your HVAC repair needs! They have the friendliest staff, amazing service, and quality work at fair prices. I had Haden and Shane come out and was very impressed by their kind nature and expertise. I would recommend them to anyone."
Patricia B on December 2024
Beltway Air Conditioning & Heating , LLC, is a family owned and operated business located in Hanover. We offer everything you need to heat, cool, and improve your indoor air quality in every corner of your home. Our high quality work with a smile is what keeps our customers satisfied. We make sure that we pay close attention to the details and take pride in delivering professional results to you at competitive rates.
"New Beltway is the best choice for your HVAC repair needs! They have the friendliest staff, amazing service, and quality work at fair prices. I had Haden and Shane come out and was very impressed by their kind nature and expertise. I would recommend them to anyone."
Patricia B on December 2024
Here at Weather Masters we pride ourselves on affordable, reliable and honest service. With free replacement estimates and competitive service rates, we do our best to keep you and your bank account comfortable.
"Great folks to work with"
Tom H on September 2023
Here at Weather Masters we pride ourselves on affordable, reliable and honest service. With free replacement estimates and competitive service rates, we do our best to keep you and your bank account comfortable.
"Great folks to work with"
Tom H on September 2023
Carroll Mechanical is an HVAC contractor that is dedicated to providing clients with the very best maintenance, repair, and installation services. We are based in Eldersburg and service customers throughout the MD region. We are a local business that is built on integrity, transparent pricing, and technical excellence. Our team of expert technicians have experience working with all major manufacturers. Our mission is to keep you comfortable and we proudly offer emergency availability where possible. If you are a homeowner, property manager, or business owner, give us a call today to learn more!
"The project (HVAC replacement) was completed on time and on budget. I particularly appreciated the time and patience provided in answering my questions related to the quote and options."
Linda M on April 2025
Carroll Mechanical is an HVAC contractor that is dedicated to providing clients with the very best maintenance, repair, and installation services. We are based in Eldersburg and service customers throughout the MD region. We are a local business that is built on integrity, transparent pricing, and technical excellence. Our team of expert technicians have experience working with all major manufacturers. Our mission is to keep you comfortable and we proudly offer emergency availability where possible. If you are a homeowner, property manager, or business owner, give us a call today to learn more!
"The project (HVAC replacement) was completed on time and on budget. I particularly appreciated the time and patience provided in answering my questions related to the quote and options."
Linda M on April 2025
Supreme Service Today is a trusted business offering Heating Cooling and Plumbing Services, and our success is based on our dedication to meeting the needs of our customers through honesty, dependability, and integrity. Our experiences lies heavily in both residential and commercial maintenance, installation, and service. We provide 24 hour emergency service to better serve our customers' needs. Our technicians are courteous, knowledgeable, and will make your needs their #1 priority. We look forward to the opportunity to doing business with you.
"We met with a few HVAC installers and Supreme Air quoted the lowest prices and gave us 3 options to choose from. No games, no pressure tactics, and no unexpected charges. They were very prompt, professional, and did a great job."
Jan and Jeremy P on July 2021
Supreme Service Today is a trusted business offering Heating Cooling and Plumbing Services, and our success is based on our dedication to meeting the needs of our customers through honesty, dependability, and integrity. Our experiences lies heavily in both residential and commercial maintenance, installation, and service. We provide 24 hour emergency service to better serve our customers' needs. Our technicians are courteous, knowledgeable, and will make your needs their #1 priority. We look forward to the opportunity to doing business with you.
"We met with a few HVAC installers and Supreme Air quoted the lowest prices and gave us 3 options to choose from. No games, no pressure tactics, and no unexpected charges. They were very prompt, professional, and did a great job."
Jan and Jeremy P on July 2021
Pipeworks Plumbing and Services, is a rapidly growing and local Heating, Air Conditioning, and Plumbing company with a focus on residential and light commercial needs. In fact, we are more than just an HVAC company - "we are in the people business servicing Heating and Air Conditioning needs". We work hard to build trust and maintain an exceptional experience for our customers building life-long relationships one day, one customer at a time.
"Pipeworks provided great service for a reasonable price. They were responsive and attentive to any questions or issues we had throughout the process."
Atiba B on June 2024
Pipeworks Plumbing and Services, is a rapidly growing and local Heating, Air Conditioning, and Plumbing company with a focus on residential and light commercial needs. In fact, we are more than just an HVAC company - "we are in the people business servicing Heating and Air Conditioning needs". We work hard to build trust and maintain an exceptional experience for our customers building life-long relationships one day, one customer at a time.
"Pipeworks provided great service for a reasonable price. They were responsive and attentive to any questions or issues we had throughout the process."
Atiba B on June 2024
When Glenmont Heating & Air Conditioning was founded 28 years ago, we had one goal in mind; providing area families, and businesses with solutions that fit their lifestyles and needs, as well as their wallets. If you have any questions about heating and air conditioning maintenance, a new HVAC system, or are looking into installing a more energy efficient system, Glenmont Heating and Air is the solution to your needs.
"Summary: Company charged me $1000+ for 2 separate service visits that did not fix my AC unit; technicians and Operations Manager are not truthful about work done; Operatiins Mngr will tell you find another HVAC company when you express dissatisfaction ….I contacted Glenmont Heating and Air Conditioning since my AC unit was not dispensing any cold air. Thermometer was set to 68° however the unit temperature was reading 77-80° (note this was the week of extreme heat wave). On 21Jun2024: Glenmont technician Roderick performed a service call. I spoke to him via phone after the call to which he told me he added refrigerant to the system. This did not fix the issue and the unit continued to not dispense cold air with the thermometer reaching 77-80° despite being set to 68°. I was charged $119 for this work. Operating Manager Tim Schindle is contradicting what the tech said and claims Roderick did not add any refrigerant. I again called Glenmont HVAC for a second service appointment. This technician claimed the coil needed to be cleaned. The second technician (Eric) then falsely reported on his report the unit temperature dropped to 68° when he left when I have photographic evidence showing the temperature in the high 70s. I waited about 24hrs as instructed for the thermostat to drop and it never did and the unit continued to not dispense cool air. I then called a supervisor (don’t recall name) who essentially told me due to the extreme temperatures everyone was experiencing HVAC issues and did not recommend any follow up service. I then had several back/forth emails with Operations manger Tim Schindler to notify him after 2 separate service visits, my air conditioning was not fixed. In the end he told me, and I quote “my system is old…we don’t know the maintenance history…it is best for both of us to find another HVAC company. He did however bill me $964 for the second service visit, which did not fix my issue. I ended up having to call another HVAC company who diagnosed the problem as a compression failure/ replaced the unit and now have cold air blowing. The second HVAC company did not understand why the 2nd technician from Glenmont Heating/Air Conditioning was changing coils and said this was not necessary to do. Second HVAC company showed me the reading of the compressor unit to which I could see no charge was registering, essentially the compressor was no longer working which was the root cause of my issue. In conclusion, I’m disappointed with Glenmont HVAC and feel they sent incompetent technicians who falsified their work. When I complained to the company and expressed my disappointment with their work (or lack there of) they told me to seek other HVAC company without fixing my AC unit but charged me $1000+. Poor business acumen and highly unethical company that needs to be held accountable for cheating customers and not performing quality work."
T C on August 2024
When Glenmont Heating & Air Conditioning was founded 28 years ago, we had one goal in mind; providing area families, and businesses with solutions that fit their lifestyles and needs, as well as their wallets. If you have any questions about heating and air conditioning maintenance, a new HVAC system, or are looking into installing a more energy efficient system, Glenmont Heating and Air is the solution to your needs.
"Summary: Company charged me $1000+ for 2 separate service visits that did not fix my AC unit; technicians and Operations Manager are not truthful about work done; Operatiins Mngr will tell you find another HVAC company when you express dissatisfaction ….I contacted Glenmont Heating and Air Conditioning since my AC unit was not dispensing any cold air. Thermometer was set to 68° however the unit temperature was reading 77-80° (note this was the week of extreme heat wave). On 21Jun2024: Glenmont technician Roderick performed a service call. I spoke to him via phone after the call to which he told me he added refrigerant to the system. This did not fix the issue and the unit continued to not dispense cold air with the thermometer reaching 77-80° despite being set to 68°. I was charged $119 for this work. Operating Manager Tim Schindle is contradicting what the tech said and claims Roderick did not add any refrigerant. I again called Glenmont HVAC for a second service appointment. This technician claimed the coil needed to be cleaned. The second technician (Eric) then falsely reported on his report the unit temperature dropped to 68° when he left when I have photographic evidence showing the temperature in the high 70s. I waited about 24hrs as instructed for the thermostat to drop and it never did and the unit continued to not dispense cool air. I then called a supervisor (don’t recall name) who essentially told me due to the extreme temperatures everyone was experiencing HVAC issues and did not recommend any follow up service. I then had several back/forth emails with Operations manger Tim Schindler to notify him after 2 separate service visits, my air conditioning was not fixed. In the end he told me, and I quote “my system is old…we don’t know the maintenance history…it is best for both of us to find another HVAC company. He did however bill me $964 for the second service visit, which did not fix my issue. I ended up having to call another HVAC company who diagnosed the problem as a compression failure/ replaced the unit and now have cold air blowing. The second HVAC company did not understand why the 2nd technician from Glenmont Heating/Air Conditioning was changing coils and said this was not necessary to do. Second HVAC company showed me the reading of the compressor unit to which I could see no charge was registering, essentially the compressor was no longer working which was the root cause of my issue. In conclusion, I’m disappointed with Glenmont HVAC and feel they sent incompetent technicians who falsified their work. When I complained to the company and expressed my disappointment with their work (or lack there of) they told me to seek other HVAC company without fixing my AC unit but charged me $1000+. Poor business acumen and highly unethical company that needs to be held accountable for cheating customers and not performing quality work."
T C on August 2024
If you’re replacing an old AC system with a new unit, you can usually clean and repair the old ductwork without having to conduct a full replacement. Cleaning HVAC ducts typically costs around $400, while repairs range from $200 to $1,000. In contrast, installing new ductwork can range from $1,000 to $5,000, making it far more costly than cleaning or fixing existing ducts. HVAC installation costs an average of $7,000 to replace a full system, so staying on top of maintenance and repairs is important.
AC cost efficiency depends on the size of your space and your long-term plans for your home. If you only need to cool a small area, a portable AC unit has a low upfront cost. Heat pumps are typically the most cost-effective option if you want to cool an entire home or improve the resale value. They provide strong cooling while being energy-efficient, which saves you money on your utility bills compared to most other AC types.
Installing a central AC unit typically takes four to eight hours if your home already has ductwork in place. However, if new ductwork needs to be installed, this can add another one to two days of labor to your project.