65/100CR Score
Ranked #1 because of its Google rating and trade focus: 5.0★ from 1,623 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 1,623 Google reviews
- Hours
- Mon–Sun 8 AM–8 PM
- Address
- 1539 Tilco Dr Unit 104, Frederick, MD 21704
Best HVAC Contractors in Frederick, MD (2026)
267 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
The short answer
- 1
Best overall in Frederick: Smock Heating & Air, CR Score 65/100; 5.0★ from 1,623 Google reviews; open 7 days a week.
- 2
Best for emergencies (open 24/7): Wenbrooke Services - Electrical, Plumbing, Heating and Air, posts 24/7 hours; ranked #2 of 267.
- 13
Most-reviewed: GAC Services, 6,908 Google reviews at 4.9★, the most of 267 ranked; ranked #13.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
267 Frederick HVAC contractors are ranked here by CR Score, from ten published factors. 74 are open 24/7, 164 open Saturdays and 114 open Sundays, based on posted hours. The median Google rating is 4.9★ across 267 rated businesses.
Top 10 HVAC contractors in Frederick at a glance
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Smock Heating & Air | 65 | 5.0★ (1,623) | Frederick | Sat · Sun · Evenings | Overall |
| 2 | Wenbrooke Services - Electrical, Plumbing, Heating and Air | 65 | 4.8★ (1,208) | Frederick | 24/7 | Emergencies |
| 3 | Larry & Sons Plumbing, Heating, Cooling, Drain & Electrical | 65 | 4.8★ (932) | Frederick | 24/7 | — |
| 4 | Markool Heating Cooling Plumbing | 65 | 4.9★ (547) | Frederick | 24/7 | — |
| 5 | Tuckers Air Conditioning, Heating & Plumbing | 65 | 4.9★ (1,614) | Frederick | Sat · Sun | — |
| 6 | United Air Temp | 64 | 4.7★ (928) | Frederick | 24/7 | — |
| 7 | May's Heating & Air Conditioning | 64 | 5.0★ (906) | Frederick | Sat · Sun | — |
| 8 | Warner Service | 64 | 4.8★ (537) | Frederick | 24/7 | — |
| 9 | Frederick Air Inc | 64 | 4.8★ (414) | Frederick | 24/7 | — |
| 10 | Urbana HVAC | 63 | 5.0★ (182) | Ballenger Creek, 2 mi away | 24/7 | — |
The 267 best HVAC contractors in Frederick, ranked
Ordered by CR Score, a 0–100 score from ten published factors. Paid placement never changes the order.
Scores below: based on 8 of 10 factors; credentials and recency not yet collected. Hatched segments mark factors we don't have yet.
Based in Frederick
65/100CR ScoreRanked #2 because of its Google rating and trade focus: 4.8★ from 1,208 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 1,208 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 4907 International Blvd #113, Frederick, MD 21703
Based in Frederick
65/100CR ScoreRanked #3 because of its Google rating and trade focus: 4.8★ from 932 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 932 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 5744 Industry Ln Suite N, Frederick, MD 21704
Based in Frederick
65/100CR ScoreRanked #4 because of its Google rating and trade focus: 4.9★ from 547 Google reviews, listed on Google as “HVAC contractor”.
- 4.9★ from 547 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 5304C Kings Ct, Frederick, MD 21703
Based in Frederick
65/100CR ScoreRanked #5 because of its Google rating and trade focus: 4.9★ from 1,614 Google reviews, listed on Google as “HVAC contractor”.
- 4.9★ from 1,614 Google reviews
- Hours
- Mon–Sun 8 AM–5 PM
- Address
- 4650 Wedgewood Blvd #102, Frederick, MD 21703
Based in Frederick
64/100CR ScoreRanked #6 because of its Google rating and trade focus: 4.7★ from 928 Google reviews, listed on Google as “HVAC contractor”.
- 4.7★ from 928 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 5305 Jefferson Pike Suite 5, Frederick, MD 21703
Based in Frederick
64/100CR ScoreRanked #7 because of its Google rating and trade focus: 5.0★ from 906 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 906 Google reviews
- Hours
- Mon–Fri 8 AM–5 PM · Sat 9 AM–1 PM · Sun 9 AM–12 PM
- Address
- 8420 Gas House Pike DD, Frederick, MD 21701
Based in Frederick
64/100CR ScoreRanked #8 because of its Google rating and trade focus: 4.8★ from 537 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 537 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 217 Monroe Ave, Frederick, MD 21701
Based in Frederick
64/100CR ScoreRanked #9 because of its Google rating and trade focus: 4.8★ from 414 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 414 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 3 King Ave, Frederick, MD 21701
#10 Urbana HVAC
Based in Ballenger Creek, 2 mi away
63/100CR ScoreRanked #10 because of its Google rating and trade focus: 5.0★ from 182 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 182 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
Based in Frederick
63/100CR ScoreRanked #11 because of its Google rating and trade focus: 4.5★ from 724 Google reviews, listed on Google as “HVAC contractor”.
- 4.5★ from 724 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 5123 Pegasus Ct Suites K-N, Frederick, MD 21704
Based in Frederick
63/100CR ScoreRanked #12 because of its Google rating and trade focus: 5.0★ from 111 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 111 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 617 W Patrick St Suite 220, Frederick, MD 21701
#13 GAC Services
Based in Gaithersburg, 23 mi away
63/100CR ScoreRanked #13 because of its Google rating and review volume: 4.9★ from 6,908 Google reviews, the most in Frederick.
- 4.9★ from 6,908 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 227 E Deer Park Dr, Gaithersburg, MD 20877
#14 closed
Based in Walkersville, 2 mi away
62/100CR ScoreRanked #14 because of its Google rating and trade focus: 4.8★ from 240 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 240 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
Based in Frederick
62/100CR ScoreRanked #15 because of its Google rating and trade focus: 4.8★ from 165 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 165 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 4959 New Design Rd, Frederick, MD 21703
#16 Alexair, LLC
Based in Frederick
61/100CR ScoreRanked #16 because of its Google rating and trade focus: 5.0★ from 119 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 119 Google reviews
- Hours
- Mon–Sun 7 AM–5 PM
- Address
- 427 Megan Ct, Frederick, MD 21701
Based in Hagerstown, 24 mi away
61/100CR ScoreRanked #17 because of its Google rating and trade focus: 4.8★ from 4,764 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 4,764 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 20 Hump Rd, Hagerstown, MD 21740
Based in Frederick
61/100CR ScoreRanked #18 because of its Google rating and trade focus: 4.9★ from 1,665 Google reviews, listed on Google as “HVAC contractor”.
- 4.9★ from 1,665 Google reviews
- Hours
- Mon–Fri 7:30 AM–4:30 PM · Sat–Sun closed
- Address
- 82A Wormans Mill Ct, Frederick, MD 21701
#19 M.E. Flow
Based in Leesburg, 23 mi away
61/100CR ScoreRanked #19 because of its Google rating and trade focus: 4.8★ from 3,718 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 3,718 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 12 Cardinal Park Dr SE STE 107, Leesburg, VA 20175
Based in Gaithersburg, 21 mi away
61/100CR ScoreRanked #20 because of its Google rating and trade focus: 4.9★ from 1,701 Google reviews, listed on Google as “HVAC contractor”.
- 4.9★ from 1,701 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 8000 Cessna Ave, Gaithersburg, MD 20879
Based in Frederick
61/100CR ScoreRanked #21 because of its Google rating and trade focus: 5.0★ from 34 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 34 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
Based in Frederick
61/100CR ScoreRanked #22 because of its Google rating and trade focus: 5.0★ from 810 Google reviews, listed on Google as “HVAC contractor”.
- 5.0★ from 810 Google reviews
- Hours
- Mon–Fri 7:30 AM–4:30 PM · Sat–Sun closed
- Address
- 13001 Penn Shop Rd, Mt Airy, MD 21771
Based in Gaithersburg, 21 mi away
61/100CR ScoreRanked #23 because of its Google rating and trade focus: 4.8★ from 2,083 Google reviews, listed on Google as “HVAC contractor”.
- 4.8★ from 2,083 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 7940 Cessna Ave, Gaithersburg, MD 20879
Based in Mount Airy, 15 mi away
60/100CR ScoreRanked #24 because of its Google rating and trade focus: 4.7★ from 852 Google reviews, listed on Google as “HVAC contractor”.
- 4.7★ from 852 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 2702 Back Acre Cir, Mt Airy, MD 21771
Based in Frederick
60/100CR ScoreRanked #25 because of its Google rating and trade focus: 4.2★ from 364 Google reviews, listed on Google as “HVAC contractor”.
- 4.2★ from 364 Google reviews
- Open 24/7
- Hours
- Open 24 hours, 7 days
- Address
- 47 E All Saints St, Frederick, MD 21701
HVAC contractors ranked #26 to #50
#1 to #25 are shown in full above. Here are #26 to #50, in CR Score order; each links to its profile. We publish the top 50 of 267 ranked HVAC contractors here; the rest are on their profiles.
Also serving Frederick
20 more HVAC contractors within 25 mi that we can't rank yet: too few reviews, or a trade we couldn't confirm. Listed A to Z.
| Business | Google rating | Distance |
|---|---|---|
| Abdul HVAC | 5.0★ (34) | 24 mi |
| AC Matthews, Roofing & Exteriors | 5.0★ (46) | In Frederick |
| AC Painting & Remodeling | 4.8★ (23) | In Frederick |
| B & E Services | 4.9★ (154) | 25 mi |
| Bob Waltz NE Plumbing & Heating | In Frederick | |
| BST Plumbing & Heating | 4.8★ (8) | 2 mi |
| Clarksburg Heating | 4.9★ (60) | 16 mi |
| ClemAIR Heating & Cooling, LLC | 5.0★ (9) | 7 mi |
| Eric Dvorak HVAC/R | In Frederick | |
| Fire n Ice Hvac, Inc | 5.0★ (90) | 24 mi |
| Forever Air Duct Cleaning | 5.0★ (6) | 11 mi |
| Frederick Electric Co LLC | 4.8★ (24) | In Frederick |
| Heating & Cooling Certified Mechanic LLC | 5.0★ (2) | 11 mi |
| Jacks Heating & AC | 5.0★ (1) | In Frederick |
| Markool Heating & Cooling | In Frederick | |
| Precision Heating & Cooling, Inc. | 2.8★ (12) | In Frederick |
| Pro Services LLC | 4.0★ (32) | In Frederick |
| Skyline Heating and Air | 5.0★ (30) | 23 mi |
| United Air Temp | 4.7★ (75) | 21 mi |
| Woodlawn Mechanical Contractors | 4.0★ (1) | In Frederick |
How much do HVAC contractors cost in Frederick?
National price ranges in USD, not adjusted for Frederick. Each row names its basis and the month we checked it.
| Job | Low | Typical | High | Basis | Checked |
|---|---|---|---|---|---|
| AC replacement | $3,887 | $5,978 | $8,073 | Per system, installed (unit plus labor); typical range of customer-reported jobs. US national range | October 2026 |
| Furnace replacement | $2,823 | $4,814 | $6,896 | Per system, installed; typical range of customer-reported jobs. US national range | October 2026 |
How to check an HVAC contractor's license in Maryland
In Maryland, Maryland State Board of Heating, Ventilation, Air-Conditioning and Refrigeration Contractors licenses Heating, ventilation, air conditioning and refrigeration work.
- Check that the status is active and the name matches the contract or truck.
- Ask for proof of insurance before work starts.
No chip usually means we have not matched a state record yet. Check the lookup yourself before you hire.
Guide checked October 2026. How we verify licenses
When to hire an HVAC contractor in Maryland
HVAC demand peaks in summer for cooling and in winter for heating. Spring and fall are the easiest times to book maintenance or a replacement.
How we ranked Frederick HVAC contractors
We scored 267 Frederick HVAC contractors on ten factors, weighted as shown. A business is ranked when its trade is confirmed and it has 3 or more Google reviews or a claimed profile. A business with no Google reviews scores zero on rating, review volume and recency. Other unknown factors are left out, not counted as zero. Scores last refreshed October 22, 2026.
Paid placement never changes a rank or score. Featured businesses are paid, labelled, limited to 3 and shown above the ranking, outside it.
| Factor | Weight | Computed from | In Frederick data |
|---|---|---|---|
| Reputation | 25% | Google star rating, adjusted for how many reviews back it | Measured |
| Credentials | 15% | Active state license, bond and workers’ comp on file | Not yet collected |
| Review volume | 10% | Number of Google reviews, compared with the most-reviewed business on the list | Measured |
| Recency | 5% | Share of reviews from the last 12 months | Not yet collected |
| Availability | 5% | Weekly open hours, Saturday, Sunday, 24/7 or same-day | Measured |
| Trade focus | 10% | How clearly the business does this trade (its Google category and name) | Measured |
| Proximity | 5% | Based in the city scores highest, less the farther away it is | Measured |
| Claimed profile | 10% | The business has claimed its ContractorsRanked profile (free or paid earn the same) | Measured |
| Partnered | 5% | The business links to ContractorsRanked from its own website with our badge, checked periodically | Measured |
| ContractorsRanked reviews | 10% | Verified customer reviews collected by ContractorsRanked: their rating and how many there are | Measured |
HVAC contractors in Frederick: frequently asked questions
Who is the best HVAC contractor in Frederick?
By CR Score, the highest-ranked HVAC contractor in Frederick, MD is Smock Heating & Air with a CR Score of 65/100. It has 5.0★ from 1,623 Google reviews. It is open 7 days a week. Wenbrooke Services - Electrical, Plumbing, Heating and Air (#2) and Larry & Sons Plumbing, Heating, Cooling, Drain & Electrical (#3) follow. We ranked 267 HVAC contractors on ten factors, last updated October 22, 2026.
How many HVAC contractors are there in Frederick?
ContractorsRanked ranks 267 HVAC contractors serving Frederick, MD. 33 of them are based in Frederick; the rest serve it from nearby towns. Another 20 within 25 mi are listed but not ranked yet. Counts are as of October 2026.
Which HVAC contractors in Frederick are open 24/7?
74 ranked HVAC contractors in Frederick post 24/7 hours. The highest-ranked are Wenbrooke Services - Electrical, Plumbing, Heating and Air (#2), Larry & Sons Plumbing, Heating, Cooling, Drain & Electrical (#3) and Markool Heating Cooling Plumbing (#4). Hours come from each business's Google listing as of October 2026, so call to confirm.
Which HVAC contractors in Frederick work on weekends?
164 of 267 ranked HVAC contractors post Saturday hours and 114 post Sunday hours. The highest-ranked open Saturdays are Smock Heating & Air (#1), Wenbrooke Services - Electrical, Plumbing, Heating and Air (#2) and Larry & Sons Plumbing, Heating, Cooling, Drain & Electrical (#3). Posted hours are office hours; crews may book weekend jobs separately.
How do I check an HVAC contractor's license in Maryland?
In Maryland, Maryland State Board of Heating, Ventilation, Air-Conditioning and Refrigeration Contractors handles licensing and covers Heating, ventilation, air conditioning and refrigeration work.
How much does ac replacement cost in Frederick?
AC replacement typically costs $3,887 to $8,073, with $5,978 typical (Per system, installed (unit plus labor); typical range of customer-reported jobs. US national range). This is a national range, not adjusted for Frederick. Prices were last checked October 2026. Get at least two written quotes before you hire.
What Google rating do Frederick HVAC contractors have?
The median Google rating among 267 rated HVAC contractors in Frederick is 4.9★, with a median of 33 reviews. GAC Services has the most, 6,908 reviews, and ranks #13. We adjust ratings for review count, so a few five-star reviews cannot top the list.
When is the best time to hire an HVAC contractor in Frederick?
HVAC demand peaks in summer for cooling and in winter for heating. Spring and fall are the easiest times to book maintenance or a replacement.
Update log for Frederick
- October 2026: CR Scores recalculated for 267 hvac contractors serving Frederick.
More HVAC contractors and Frederick pages
HVAC contractors near Frederick
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- HVAC contractors in Walkersville, MD231 ranked
- HVAC contractors in Urbana, MD385 ranked
- HVAC contractors in Green Valley, MD454 ranked
- HVAC contractors in Linganore, MD311 ranked
- HVAC contractors in Brunswick, MD245 ranked
- HVAC contractors in Mount Airy, MD442 ranked
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Other trades in Frederick
- Roofers in Frederick863 ranked
- Plumbers in Frederick221 ranked
- Electricians in Frederick175 ranked
- General contractors in Frederick381 ranked
- Painters in Frederick69 ranked
- Landscapers in Frederick95 ranked
- Handymen in Frederick37 ranked
- Kitchen remodelers in Frederick256 ranked
- Bathroom remodelers in Frederick256 ranked
- Flooring contractors in Frederick141 ranked
- Tile installers in Frederick19 ranked
- Drywall contractors in Frederick5 ranked
- Concrete contractors in Frederick67 ranked
- Fence contractors in Frederick60 ranked
- Deck builders in Frederick152 ranked
- Siding contractors in Frederick388 ranked
- Window installers in Frederick386 ranked
- Gutter installers in Frederick99 ranked
- Insulation contractors in Frederick34 ranked
- Solar installers in Frederick100 ranked
- Garage door repair companies in Frederick38 ranked
- Foundation repair companies in Frederick111 ranked
- Tree services in Frederick111 ranked
- Masonry contractors in Frederick69 ranked
- Water damage restoration companies in Frederick493 ranked
- Home builders in Frederick558 ranked
- Demolition contractors in Frederick20 ranked
- All contractors in Frederick