Ranked #1 because of its Google rating and review volume: 4.9★ from 6,908 Google reviews, the most in Linganore.
- 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
311 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Linganore: GAC Services, CR Score 63/100; 4.9★ from 6,908 Google reviews; open 24/7.
Best for emergencies (open 24/7): One Hour Air Conditioning & Heating® of Mount Airy, posts 24/7 hours; ranked #3 of 311.
Most-reviewed: F.H. Furr Plumbing, Heating, Air Conditioning & Electrical, 5,985 Google reviews at 4.7★, the most of 311 ranked after GAC Services; ranked #18.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
311 Linganore HVAC contractors are ranked here by CR Score, from ten published factors. 84 are open 24/7, 176 open Saturdays and 128 open Sundays, based on posted hours. The median Google rating is 4.9★ across 311 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | GAC Services | 63 | 4.9★ (6,908) | Gaithersburg, 21 mi away | 24/7 | Overall |
| 2 | Smock Heating & Air | 63 | 5.0★ (1,623) | Frederick, 10 mi away | Sat · Sun · Evenings | — |
| 3 | One Hour Air Conditioning & Heating® of Mount Airy | 62 | 4.7★ (852) | Mount Airy, 6 mi away | 24/7 | Emergencies |
| 4 | Wenbrooke Services - Electrical, Plumbing, Heating and Air | 62 | 4.8★ (1,208) | Frederick, 13 mi away | 24/7 | — |
| 5 | Larry & Sons Plumbing, Heating, Cooling, Drain & Electrical | 62 | 4.8★ (932) | Frederick, 12 mi away | 24/7 | — |
| 6 | May's Heating & Air Conditioning | 62 | 5.0★ (906) | Frederick, 9 mi away | Sat · Sun | — |
| 7 | Presidential, Inc. | 62 | 4.9★ (1,701) | Gaithersburg, 19 mi away | 24/7 | — |
| 8 | Warner Service | 61 | 4.8★ (537) | Frederick, 10 mi away | 24/7 | — |
| 9 | F.H. Furr Plumbing, Heating, Air Conditioning & Electrical | 61 | 4.7★ (1,847) | Eldersburg, 15 mi away | 24/7 | — |
| 10 | Tuckers Air Conditioning, Heating & Plumbing | 61 | 4.9★ (1,614) | Frederick, 13 mi away | Sat · Sun | — |
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.
Ranked #1 because of its Google rating and review volume: 4.9★ from 6,908 Google reviews, the most in Linganore.
Based in Frederick, 10 mi away
Ranked #2 because of its Google rating and trade focus: 5.0★ from 1,623 Google reviews, listed on Google as “HVAC contractor”.
Based in Mount Airy, 6 mi away
Ranked #3 because of its Google rating and trade focus: 4.7★ from 852 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 13 mi away
Ranked #4 because of its Google rating and trade focus: 4.8★ from 1,208 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 12 mi away
Ranked #5 because of its Google rating and trade focus: 4.8★ from 932 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 9 mi away
Ranked #6 because of its Google rating and trade focus: 5.0★ from 906 Google reviews, listed on Google as “HVAC contractor”.
Based in Gaithersburg, 19 mi away
Ranked #7 because of its Google rating and trade focus: 4.9★ from 1,701 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 10 mi away
Ranked #8 because of its Google rating and trade focus: 4.8★ from 537 Google reviews, listed on Google as “HVAC contractor”.
Based in Eldersburg, 15 mi away
Ranked #9 because of its Google rating and trade focus: 4.7★ from 1,847 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 13 mi away
Ranked #10 because of its Google rating and trade focus: 4.9★ from 1,614 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 10 mi away
Ranked #11 because of its Google rating and trade focus: 4.8★ from 414 Google reviews, listed on Google as “HVAC contractor”.
Based in Gaithersburg, 19 mi away
Ranked #12 because of its Google rating and trade focus: 4.8★ from 2,083 Google reviews, listed on Google as “HVAC contractor”.
Based in Westminster, 16 mi away
Ranked #13 because of its Google rating and trade focus: 4.9★ from 679 Google reviews, listed on Google as “HVAC contractor”.
Based in Westminster, 15 mi away
Ranked #14 because of its Google rating and trade focus: 4.9★ from 580 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 15 mi away
Ranked #15 because of its Google rating and trade focus: 4.9★ from 547 Google reviews, listed on Google as “HVAC contractor”.
Based in Gaithersburg, 19 mi away
Ranked #16 because of its Google rating and trade focus: 4.8★ from 1,700 Google reviews, listed on Google as “HVAC contractor”.
Based in Ballenger Creek, 11 mi away
Ranked #17 because of its Google rating and trade focus: 5.0★ from 182 Google reviews, listed on Google as “HVAC contractor”.
Based in Rockville, 24 mi away
Ranked #18 because of its Google rating and trade focus: 4.7★ from 5,985 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 15 mi away
Ranked #19 because of its Google rating and trade focus: 4.7★ from 928 Google reviews, listed on Google as “HVAC contractor”.
Based in Walkersville, 11 mi away
Ranked #20 because of its Google rating and trade focus: 4.8★ from 240 Google reviews, listed on Google as “HVAC contractor”.
Based in Westminster, 15 mi away
Ranked #21 because of its Google rating and review volume: 5.0★ from 2,777 Google reviews.
Based in Frederick, 12 mi away
Ranked #22 because of its Google rating and trade focus: 4.5★ from 724 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 12 mi away
Ranked #23 because of its Google rating and trade focus: 5.0★ from 111 Google reviews, listed on Google as “HVAC contractor”.
Based in Gaithersburg, 19 mi away
Ranked #24 because of its Google rating and trade focus: 4.8★ from 666 Google reviews, listed on Google as “HVAC contractor”.
Based in Reisterstown, 21 mi away
Ranked #25 because of its Google rating and trade focus: 4.9★ from 469 Google reviews, listed on Google as “HVAC contractor”.
#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 311 ranked HVAC contractors here; the rest are on their profiles.
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 |
|---|---|---|
| A Blessing Mechanical, LLC | 5.0★ (2) | 24 mi |
| A Quality HVAC | 5.0★ (2) | 15 mi |
| Air Zone Systems, Inc | 5.0★ (2) | 12 mi |
| AM/PM Emergency Services a division of Robert E Clubb & Associates | 5.0★ (2) | 7 mi |
| Apple Plumbing, Heating, & Air | 5.0★ (216) | 14 mi |
| Beltway Air Conditioning, Heating & Plumbing | 4.9★ (90) | 24 mi |
| Brothers HVAC LLC | 4.9★ (76) | 23 mi |
| Davis Plumbing & Heating Inc | 5.0★ (2) | 21 mi |
| garagedoorsrepairellicottcitymd | 5.0★ (2) | 25 mi |
| Heating & Cooling Certified Mechanic LLC | 5.0★ (2) | 22 mi |
| JLB Mechanical Heating & Cooling, Inc. | 5.0★ (16) | 16 mi |
| Long Mechanical Services LLC | 5.0★ (19) | 14 mi |
| Mayne Source Heating & Air | 5.0★ (2) | 2 mi |
| P W Scholl Plumbing & Heating Inc | 5.0★ (2) | 14 mi |
| Palmer Heating and Cooling | 5.0★ (2) | 24 mi |
| Precision Heating & Cooling, Inc. | 2.8★ (12) | 5 mi |
| Right-A-Way Heating & Cooling | 5.0★ (17) | 10 mi |
| Siegman Forced Air Systems, Inc. | 4.7★ (30) | 15 mi |
| United Air Temp | 4.7★ (75) | 21 mi |
| Vito Services | 4.7★ (1,351) | 24 mi |
National price ranges in USD, not adjusted for Linganore. 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 |
In Maryland, Maryland State Board of Heating, Ventilation, Air-Conditioning and Refrigeration Contractors licenses Heating, ventilation, air conditioning and refrigeration work.
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
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.
We scored 311 Linganore 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 Linganore 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 |