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Find Ducts & vents installers and replacers in Knoxville

Avatar for TriState Home Services

TriState Home Services

82A Wormans Mill Ct
4.64(
195
)
Approved Pro

TriState Home Services

82A Wormans Mill Ct
4.64(
195
)
Approved Pro
Customers say: Super punctual
563 local quotes requested
76 years of experience

If you are looking for a HVAC Contractor, a Plumbing Contractor, or an Electrical Contractor to provide you with great service, you've come to the right place. We provide heating services, air conditioning services, plumbing services, and electrical services to our customers in Frederick and the surrounding Counties, the Pan Handle of West Virginia, and Northern Virginia, from our offices located in Frederick MD. With 3 generations of experience in providing heating, air conditioning, plumbing, and electrical services, we are dedicated to providing the best possible products and services for you, and your family.

"Great service very prompt and easy to work with."

Randy W on May 2025

If you are looking for a HVAC Contractor, a Plumbing Contractor, or an Electrical Contractor to provide you with great service, you've come to the right place. We provide heating services, air conditioning services, plumbing services, and electrical services to our customers in Frederick and the surrounding Counties, the Pan Handle of West Virginia, and Northern Virginia, from our offices located in Frederick MD. With 3 generations of experience in providing heating, air conditioning, plumbing, and electrical services, we are dedicated to providing the best possible products and services for you, and your family.

"Great service very prompt and easy to work with."

Randy W on May 2025


Avatar for Relax HVAC, Inc.

Relax HVAC, Inc.

43330 Junction Plz
5.00(
28
)
Approved Pro

Relax HVAC, Inc.

43330 Junction Plz
5.00(
28
)
Approved Pro
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
626 local quotes requested

Relax HVAC, Inc. is a fully insured and licensed heating and air conditioning firm in Ashburn, Virginia, composed of Master Technicians led by Kamal. He and his team provide round-the-clock emergency services for residential and commercial customers, including those in the Iranian, Arabic, and Palestinian communities. With more than 25 years of experience in providing air conditioning services, Kamal takes pride in making customers feel good about his company. He does this by giving them quality and honest services at great prices. His services are approved and recommended by the Loudoun County Fire Department.

"My AC failed and I had limited time to find a good solution, I made a phone call to Relax HVAC based on the online reviews and it was a great decision. Nasser came to check the situation, he gave a very detailed and comprehensive overview of the situation and provided with the options I had. I decided to replace the unit, Nasser went above and beyond to find a unit delivery service but there was nothing available over the weekend so this gentleman went for unit pick up himself and finished the installation within a day from my initial call. Moreover, the provided price was very reasonable.I can't be more happy with the outcome and highly recommend Relax HVAC"

Navid P on July 2024

Relax HVAC, Inc. is a fully insured and licensed heating and air conditioning firm in Ashburn, Virginia, composed of Master Technicians led by Kamal. He and his team provide round-the-clock emergency services for residential and commercial customers, including those in the Iranian, Arabic, and Palestinian communities. With more than 25 years of experience in providing air conditioning services, Kamal takes pride in making customers feel good about his company. He does this by giving them quality and honest services at great prices. His services are approved and recommended by the Loudoun County Fire Department.

"My AC failed and I had limited time to find a good solution, I made a phone call to Relax HVAC based on the online reviews and it was a great decision. Nasser came to check the situation, he gave a very detailed and comprehensive overview of the situation and provided with the options I had. I decided to replace the unit, Nasser went above and beyond to find a unit delivery service but there was nothing available over the weekend so this gentleman went for unit pick up himself and finished the installation within a day from my initial call. Moreover, the provided price was very reasonable.I can't be more happy with the outcome and highly recommend Relax HVAC"

Navid P on July 2024


Avatar for Presidential Heating & Air Conditioning

Presidential Heating & Air Conditioning

8000 Cessna Ave
4.65(
430
)
Approved Pro

Presidential Heating & Air Conditioning

8000 Cessna Ave
4.65(
430
)
Approved Pro
Customers say: Super punctual
538 local quotes requested
43 years of experience

You and your family deserve to receive the best care and the best service. Not every heating & A/C company gives you the quality people and care that Presidential does. We offer 40 Years of Award-Winning Quality People, Quality Installation, and Quality Service. Delivering this quality service and care for your home is our commitment to you! Family-owned and operated, Presidential specializes in residential and light commercial service and installation throughout MD, VA & DC. Ask us about our system replacement specials and The Advantage Maintenance Plan for preferred VIP service. Presidential has been awarded the Carrier Factory Authorized Dealer Award and is a member of the ACCA (Air Conditioning Contractors of America) and the Quality One service network.

"Came for routine maintenance and estimate for a humidifier. The customer service was excellent, from scheduling to the job itself. Glad I found them and expect to now be a long term customer."

Michael J on June 2025

You and your family deserve to receive the best care and the best service. Not every heating & A/C company gives you the quality people and care that Presidential does. We offer 40 Years of Award-Winning Quality People, Quality Installation, and Quality Service. Delivering this quality service and care for your home is our commitment to you! Family-owned and operated, Presidential specializes in residential and light commercial service and installation throughout MD, VA & DC. Ask us about our system replacement specials and The Advantage Maintenance Plan for preferred VIP service. Presidential has been awarded the Carrier Factory Authorized Dealer Award and is a member of the ACCA (Air Conditioning Contractors of America) and the Quality One service network.

"Came for routine maintenance and estimate for a humidifier. The customer service was excellent, from scheduling to the job itself. Glad I found them and expect to now be a long term customer."

Michael J on June 2025


Avatar for GAC Services

GAC Services

227 E Deer Park Dr
4.80(
279
)
Approved Pro

GAC Services

227 E Deer Park Dr
4.80(
279
)
Approved Pro
Customers say: Quick response
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
4619 local quotes requested

GAC Services is a residential cooling, heating, and electrical contractor setting new standards in the Maryland HVAC and electric market. Since 1970, we’ve developed a strong reputation for providing the Montgomery County and Frederick County areas with reliable cooling and heating services. In 2014, we expanded our service offerings to include electrical services—allowing us to offer our customers the same great service in a new area of business. Additional DBA: Gaithersburg Heating & Cooling

"Highly professional, knowledgeable and well behaved technician. Prices offered were good too. I definitely recommend the company."

Deepak K on February 2025

GAC Services is a residential cooling, heating, and electrical contractor setting new standards in the Maryland HVAC and electric market. Since 1970, we’ve developed a strong reputation for providing the Montgomery County and Frederick County areas with reliable cooling and heating services. In 2014, we expanded our service offerings to include electrical services—allowing us to offer our customers the same great service in a new area of business. Additional DBA: Gaithersburg Heating & Cooling

"Highly professional, knowledgeable and well behaved technician. Prices offered were good too. I definitely recommend the company."

Deepak K on February 2025


Avatar for JDL HVAC & Plumbing Services

JDL HVAC & Plumbing Services

14300 Cherry Lane
4.50(
113
)
Approved Pro

JDL HVAC & Plumbing Services

14300 Cherry Lane
4.50(
113
)
Approved Pro
Customers say: Super punctual
2353 local quotes requested
13 years of experience

JDL HVAC & Plumbing Services LLC offers a wide range of services to meet your HVAC & Plumbing needs. ​ With offices in both Maryland & Virginia, we serve both residential and commercial clients and specialize in offering a variety of money-saving solutions. Combined with our use of the highest quality parts and equipment and our dedication to delivering exceptional service, we have become known as the HVAC & Plumbing contractor of choice in the DMV area! The mission of JDL is to provide honest, reliable service that stands head and shoulders above the rest. We continually strive to exceed expectations by ensuring that each client receives the very best service from our friendly and knowledgeable HVAC/Plumbing service technicians. No matter what you need you can rely on JDL to provide an unparalleled knowledge, experience and expertise!

"They did a good job"

Richard T on June 2024

JDL HVAC & Plumbing Services LLC offers a wide range of services to meet your HVAC & Plumbing needs. ​ With offices in both Maryland & Virginia, we serve both residential and commercial clients and specialize in offering a variety of money-saving solutions. Combined with our use of the highest quality parts and equipment and our dedication to delivering exceptional service, we have become known as the HVAC & Plumbing contractor of choice in the DMV area! The mission of JDL is to provide honest, reliable service that stands head and shoulders above the rest. We continually strive to exceed expectations by ensuring that each client receives the very best service from our friendly and knowledgeable HVAC/Plumbing service technicians. No matter what you need you can rely on JDL to provide an unparalleled knowledge, experience and expertise!

"They did a good job"

Richard T on June 2024


F.H. Furr Plumbing Heating & Air Conditioning Inc

685 Lofstrand Lane
4.33(
15
)
Approved Pro

F.H. Furr Plumbing Heating & Air Conditioning Inc

685 Lofstrand Lane
4.33(
15
)
Approved Pro
Customers say: Super punctual
3965 local quotes requested
44 years of experience

Whether you need a repair, preventive maintenance, or replacement, we are your plumbing, heating, and air conditioning service provider in the northern Virginia and surrounding areas. We invite you to give us a call!

"Nice, reliable, and responded immediately."

Ethan Q on January 2025

Whether you need a repair, preventive maintenance, or replacement, we are your plumbing, heating, and air conditioning service provider in the northern Virginia and surrounding areas. We invite you to give us a call!

"Nice, reliable, and responded immediately."

Ethan Q on January 2025


Avatar for Cyprus Air Heating, Cooling and Fireplaces

Cyprus Air Heating, Cooling and Fireplaces

7525 Richmond Hwy
4.06(
491
)
Approved Pro

Cyprus Air Heating, Cooling and Fireplaces

7525 Richmond Hwy
4.06(
491
)
Approved Pro
Customers say: Quality work
2526 local quotes requested
58 years of experience

FREE IN-HOME ESTIMATES | GET A FREE AIR CONDITIONER Cyprus Air Heating & Cooling is your single resource for all your home comfort needs, from tailoring your ideal comfort system to installation, service and beyond. Cyprus Air installs and repairs a variety of Heating & Cooling equipment. With over 56 years of experience in the business, we also offer other home improvement and indoor comfort services such as Gas Fireplaces & Gas logs, and Duct Cleaning. With so many years of design, and installations in Northern Virginia, DC and Maryland, Cyprus Air offers its service oriented expertise and reliability to ensure the high quality standards that architects, engineers, and homeowners have come to rely on from one of the industry leaders.

"I called to get an inspection done on my AC unit and was quoted $90 for the inspection plus $120 an hr for ADDITIONAL hrs. I ASKED when do I know when the “additional hrs start”, He stated that the tech would let me know once the inspection was done and then at that time he would let me know if there was work that needed to be fixed or if there was nothing then the service would end and I would only have to pay the $90. They charged me $210 for the inspection. I called and requested that we both listen to the call (Because all calls are recorded) They played the call, heard what the rep said and then stated they would get back to me. When I finally reached them again (they never called me back), they stated I would not get a refund, then replayed the call cutting out the part when the rep stated clearly that the service was only $90. They not only GASLIGHTED me, but they altered the recording. $120 may not matter to most but it sure matters to me."

Kay H on June 2025

FREE IN-HOME ESTIMATES | GET A FREE AIR CONDITIONER Cyprus Air Heating & Cooling is your single resource for all your home comfort needs, from tailoring your ideal comfort system to installation, service and beyond. Cyprus Air installs and repairs a variety of Heating & Cooling equipment. With over 56 years of experience in the business, we also offer other home improvement and indoor comfort services such as Gas Fireplaces & Gas logs, and Duct Cleaning. With so many years of design, and installations in Northern Virginia, DC and Maryland, Cyprus Air offers its service oriented expertise and reliability to ensure the high quality standards that architects, engineers, and homeowners have come to rely on from one of the industry leaders.

"I called to get an inspection done on my AC unit and was quoted $90 for the inspection plus $120 an hr for ADDITIONAL hrs. I ASKED when do I know when the “additional hrs start”, He stated that the tech would let me know once the inspection was done and then at that time he would let me know if there was work that needed to be fixed or if there was nothing then the service would end and I would only have to pay the $90. They charged me $210 for the inspection. I called and requested that we both listen to the call (Because all calls are recorded) They played the call, heard what the rep said and then stated they would get back to me. When I finally reached them again (they never called me back), they stated I would not get a refund, then replayed the call cutting out the part when the rep stated clearly that the service was only $90. They not only GASLIGHTED me, but they altered the recording. $120 may not matter to most but it sure matters to me."

Kay H on June 2025


Avatar for Holtzople Heating, Air Conditioning, & Electrical Services

Holtzople Heating, Air Conditioning, & Electrical Services

16424 Old Frederick Rd
4.87(
188
)
Approved Pro

Holtzople Heating, Air Conditioning, & Electrical Services

16424 Old Frederick Rd
4.87(
188
)
Approved Pro
Super Service Award
Customers say: Quality work
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
298 local quotes requested

Holtzople is a leading HVAC company in Frederick, Carroll, and Washington counties in Maryland, as well as Adams and small parts of Franklin & York counties in Pennsylvania, featuring all the top brands in the Heating and Cooling industry, such as Trane, Bryant, Lennox, Carrier, ClimateMaster, WaterFurnace, and more. We recently added an electrical department to our services, making us your one-stop shop for HVAC and electrical needs. Quality is Not Expensive, It's Priceless!

"Ok, some neighbors complaint how expensive Holtzople can be, but boy, you don’t get such quality and service elsewhere. We have had them for decades and this year needed a new unit because ours was so old, and this latest model was installed in three days, right before that June heat wave hit. And you get two free inspections following installation to see that it is working optimally with the most incredible work force ever—on time, competent, polite, caring and oh so concerned that you are a satisfied customer. For our money, they don’t come any better! And you’d be amazed at the nos. of people who agree with us!"

Leslie M on August 2025

Holtzople is a leading HVAC company in Frederick, Carroll, and Washington counties in Maryland, as well as Adams and small parts of Franklin & York counties in Pennsylvania, featuring all the top brands in the Heating and Cooling industry, such as Trane, Bryant, Lennox, Carrier, ClimateMaster, WaterFurnace, and more. We recently added an electrical department to our services, making us your one-stop shop for HVAC and electrical needs. Quality is Not Expensive, It's Priceless!

"Ok, some neighbors complaint how expensive Holtzople can be, but boy, you don’t get such quality and service elsewhere. We have had them for decades and this year needed a new unit because ours was so old, and this latest model was installed in three days, right before that June heat wave hit. And you get two free inspections following installation to see that it is working optimally with the most incredible work force ever—on time, competent, polite, caring and oh so concerned that you are a satisfied customer. For our money, they don’t come any better! And you’d be amazed at the nos. of people who agree with us!"

Leslie M on August 2025


Avatar for McCrea Heating & Air Conditioning Services of PA

McCrea Heating & Air Conditioning Services of PA

151 Commerce Ave
4.78(
306
)
Approved Pro

McCrea Heating & Air Conditioning Services of PA

151 Commerce Ave
4.78(
306
)
Approved Pro
Customers say: Super punctual
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
291 local quotes requested

McCrea is a family owned business that has served our area since 1936. Financing and rebates are available on Trane systems installed by McCrea. Resistrictions apply and these are limited time offers call for details. "Its hard to stop a Trane"

"We bought a new construction and McCrea installed the HVAC. Home inspection identified the heat pump was not working in Oct. 2020. McCrea identified it was due to leaking refrigerants and promise fixed the issue. Our electric bill was extremely high the following two months and the heat pump was not cooling in Spring 2021. McCrea sent technician and again repaired the system. Bought their maintenance plan. We had 4+ repairs plus regular tune up in the past two years. Last week the heat pump stopped cooling again. We are out of labor warranty and charge us with $89 diagnostic cost after membership discount. It took three days for them to send someone to check while we suffering 90F in our house. They identified the compressor dead and need replacement. They charge $1900 for labor after membership discount. Most likely cause of the compressor failure is "suicide" with assistance. Low refrigerant at beginning and over change in later repairs likely contributed the short life."

Wei X on July 2023

McCrea is a family owned business that has served our area since 1936. Financing and rebates are available on Trane systems installed by McCrea. Resistrictions apply and these are limited time offers call for details. "Its hard to stop a Trane"

"We bought a new construction and McCrea installed the HVAC. Home inspection identified the heat pump was not working in Oct. 2020. McCrea identified it was due to leaking refrigerants and promise fixed the issue. Our electric bill was extremely high the following two months and the heat pump was not cooling in Spring 2021. McCrea sent technician and again repaired the system. Bought their maintenance plan. We had 4+ repairs plus regular tune up in the past two years. Last week the heat pump stopped cooling again. We are out of labor warranty and charge us with $89 diagnostic cost after membership discount. It took three days for them to send someone to check while we suffering 90F in our house. They identified the compressor dead and need replacement. They charge $1900 for labor after membership discount. Most likely cause of the compressor failure is "suicide" with assistance. Low refrigerant at beginning and over change in later repairs likely contributed the short life."

Wei X on July 2023


Avatar for Petro Home Services

Petro Home Services

650 Knowles Ave
4.44(
98
)
Approved Pro

Petro Home Services

650 Knowles Ave
4.44(
98
)
Approved Pro
Customers say: True professional
8728 local quotes requested
122 years of experience

With over 100 years experience, we know how to keep you comfortable, safe and help you save on energy costs. Our local 24/7 customer service and support means automatic heating oil deliveries and our service response is always fast. We never run out of heating oil plus our pricing and payment plans are designed to help you manage your costs all year round. Experience the Petro difference today!

"Worst service I’ve ever have experienced. They wanted to sell me the product, never told me that there was an early termination fee and another penalty for an initial offer they gave me. Had double charges every month, once for the oil they provided (which they never told me they were going to provide before coming. They just came without my knowledge and then I find a high amount bill) and another for an “automatic payment” for 500 that they never could explain. The didn’t even fix this issue and it kept happening every month even after I cancelled the service. Then having to call them is a hastié for the refund of the 500. Stay away of this company"

Axel R on January 2023

With over 100 years experience, we know how to keep you comfortable, safe and help you save on energy costs. Our local 24/7 customer service and support means automatic heating oil deliveries and our service response is always fast. We never run out of heating oil plus our pricing and payment plans are designed to help you manage your costs all year round. Experience the Petro difference today!

"Worst service I’ve ever have experienced. They wanted to sell me the product, never told me that there was an early termination fee and another penalty for an initial offer they gave me. Had double charges every month, once for the oil they provided (which they never told me they were going to provide before coming. They just came without my knowledge and then I find a high amount bill) and another for an “automatic payment” for 500 that they never could explain. The didn’t even fix this issue and it kept happening every month even after I cancelled the service. Then having to call them is a hastié for the refund of the 500. Stay away of this company"

Axel R on January 2023

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FAQs for ducts & vents installation and replacement projects in Knoxville, MD

Return air vents aren't required in every room, but proper placement is essential for system efficiency. According to industry standards, you'll need one return vent for every 100 to 150 square feet of living space. Ideally, each room would have its own return vent, especially larger rooms exceeding 100 square feet. 

Without adequate return airflow, your HVAC system works harder, energy costs increase, and comfort decreases. A professional assessment can determine the optimal number and placement of return vents for your specific home layout.

Signs that your home needs additional return air vents include rooms that feel consistently stuffy, noticeable temperature variations between rooms, doors that slam shut when the HVAC system operates, or unexpectedly high energy bills. Excessive dust accumulation around supply vents can also indicate inadequate return airflow. 

If you experience these issues, consulting with an HVAC professional can help determine if adding return vents would improve your system's performance.

Supply vents deliver conditioned air into your living spaces, while return air vents draw room air back to your HVAC system for reconditioning. Supply vents push treated air into rooms, while return vents pull air from rooms back toward your heating and cooling equipment. 

Both components are essential for proper air circulation and system balance. Without sufficient return capacity, your HVAC system may experience pressure imbalances that reduce efficiency and comfort.

You should inspect and clean your return air vents at least once annually, according to industry recommendations. However, homes with pets, allergy sufferers, or noticeable dust buildup may benefit from more frequent cleaning. 

Regular maintenance helps maintain good indoor air quality and ensures your HVAC system operates efficiently. Professional duct cleaning, which addresses the entire system beyond just the visible vents, is recommended every few years, depending on your home's specific conditions.

The Knoxville, MD homeowners’ guide to ducts & vents installations and replacements

From average costs to expert advice, get all the answers you need to get your job done.

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