603 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Derry: Heritage Home Service, CR Score 94/100; 4.8★ from 7,956 Google reviews; open 24/7.
Best for emergencies (open 24/7): High Ground Service Pros - Plumbers Electricians & HVAC Technicians, posts 24/7 hours; ranked #2 of 603.
Most-reviewed: Heritage Home Service, 3,352 Google reviews at 4.8★, the most of 603 ranked after Heritage Home Service; ranked #18.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
603 Derry HVAC contractors are ranked here by CR Score, from 8 published factors. 164 are open 24/7, 289 open Saturdays and 206 open Sundays, based on posted hours. The median Google rating is 4.9★ across 603 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Heritage Home Service | 94 | 4.8★ (7,956) | Auburn, 6 mi away | 24/7 | Overall |
| 2 | High Ground Service Pros - Plumbers Electricians & HVAC Technicians | 92 | 4.9★ (2,303) | Manchester, 11 mi away | 24/7 | Emergencies |
| 3 | Southern New Hampshire Plumbing and Heating | 91 | 4.8★ (433) | Londonderry, 2 mi away | 24/7 | — |
| 4 | Patriot Oil Burner Service | 90 | 5.0★ (263) | Chester, 7 mi away | 24/7 | — |
| 5 | Walley's Heating & Air | 90 | 4.9★ (793) | Nashua, 11 mi away | 24/7 | — |
| 6 | Derry Plumbing & Heating | 90 | 4.8★ (176) | Derry | 24/7 | — |
| 7 | LHR Plumbing Heating Cooling and Electric | 90 | 4.9★ (454) | Manchester, 9 mi away | 24/7 | — |
| 8 | Northeast Heating & Cooling | 89 | 5.0★ (449) | Haverhill, 13 mi away | 24/7 | — |
| 9 | A.J. LeBlanc Heating, A/C, Plumbing & Electrical | 89 | 4.8★ (683) | Bedford, 10 mi away | 24/7 | — |
| 10 | MillTown Plumbing, Heating, Cooling and Electrical | 89 | 4.8★ (2,927) | Chelmsford, 18 mi away | 24/7 | — |
Ordered by CR Score, a 0–100 score from 8 published factors. Paid placement never changes the order.
Scores below: based on 6 of 8 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: 4.8★ from 7,956 Google reviews, the most Google reviews on this list (7,956).
Based in Manchester, 11 mi away
Ranked #2 because of its Google rating and availability: 4.9★ from 2,303 Google reviews, open 24/7.
Based in Londonderry, 2 mi away
Ranked #3 because of its Google rating and availability: 4.8★ from 433 Google reviews, open 24/7.
Based in Chester, 7 mi away
Ranked #4 because of its Google rating and availability: 5.0★ from 263 Google reviews, open 24/7.
Based in Nashua, 11 mi away
Ranked #5 because of its Google rating and availability: 4.9★ from 793 Google reviews, open 24/7.
Based in Derry
Ranked #6 because of its Google rating and availability: 4.8★ from 176 Google reviews, open 24/7.
Based in Manchester, 9 mi away
Ranked #7 because of its Google rating and availability: 4.9★ from 454 Google reviews, open 24/7.
Based in Haverhill, 13 mi away
Ranked #8 because of its Google rating and availability: 5.0★ from 449 Google reviews, open 24/7.
Based in Bedford, 10 mi away
Ranked #9 because of its Google rating and availability: 4.8★ from 683 Google reviews, open 24/7.
Based in Chelmsford, 18 mi away
Ranked #10 because of its Google rating and availability: 4.8★ from 2,927 Google reviews, open 24/7.
Based in Milford, 19 mi away
Ranked #11 because of its Google rating and availability: 4.9★ from 1,832 Google reviews, open 24/7.
Based in Billerica, 15 mi away
Ranked #12 because of its Google rating and availability: 4.8★ from 1,626 Google reviews, open 24/7.
Based in Nashua, 11 mi away
Ranked #13 because of its Google rating and availability: 4.9★ from 348 Google reviews, open 24/7.
Based in Fitchburg, 19 mi away
Ranked #14 because of its Google rating and availability: 4.9★ from 1,275 Google reviews, open 24/7.
Based in North Andover, 17 mi away
Ranked #15 because of its Google rating and availability: 5.0★ from 562 Google reviews, open 24/7.
Based in Manchester, 8 mi away
Ranked #16 because of its Google rating and availability: 4.9★ from 167 Google reviews, open 24/7.
Based in Manchester, 9 mi away
Ranked #17 because of its Google rating and availability: 4.7★ from 598 Google reviews, open 24/7.
Based in Wilmington, 22 mi away
Ranked #18 because of its Google rating and availability: 4.8★ from 3,352 Google reviews, open 24/7.
Based in Billerica, 19 mi away
Ranked #19 because of its Google rating and availability: 5.0★ from 476 Google reviews, open 24/7.
Based in Chelmsford, 20 mi away
Ranked #20 because of its Google rating and availability: 5.0★ from 443 Google reviews, open 24/7.
Based in Litchfield, 14 mi away
Ranked #21 because of its Google rating and availability: 4.9★ from 320 Google reviews, open 24/7.
Based in Derry
Ranked #22 because of its Google rating and availability: 5.0★ from 18 Google reviews, open 24/7.
Based in Derry
Ranked #23 because of its Google rating and availability: 4.5★ from 94 Google reviews, open 24/7.
Based in Concord, 20 mi away
Ranked #24 because of its Google rating and availability: 4.9★ from 539 Google reviews, open 24/7.
Based in Methuen, 14 mi away
Ranked #25 because of its Google rating and availability: 4.8★ from 313 Google reviews, open 24/7.
#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 603 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 |
|---|---|---|
| Advanced Refrigeration & AC | 3.0★ (2) | 10 mi |
| American Home Services | In Derry | |
| B A Carson Plumbing & Heating Inc | In Derry | |
| Buonagurio HVAC | 5.0★ (2) | 13 mi |
| D&M Electric | 4.9★ (34) | In Derry |
| Fusion Mechanical Services | 3.0★ (2) | 10 mi |
| Georges Heating and Cooling | 4.3★ (82) | 6 mi |
| Harley Weymouth Plumbing & Heating | 5.0★ (2) | 12 mi |
| HVAC Unlimited LLC | 5.0★ (2) | 12 mi |
| J. Griffin Heating & Plumbing Inc | 5.0★ (643) | 24 mi |
| JAIS PLUMBING AND HEATING | 5.0★ (1) | In Derry |
| Krafton plumbing and heating | 5.0★ (2) | 11 mi |
| LHR Plumbing, Heating & AC Repair | 4.9★ (128) | 12 mi |
| Mikey Pipes Plumbing & Heating LLC | 5.0★ (2) | 11 mi |
| Northeast Infravision | In Derry | |
| Patriot Heating & Cooling, LLC | 4.8★ (174) | 13 mi |
| Purple HVAC | 5.0★ (2) | 11 mi |
| SERVPRO of Derry/Londonderry | 4.8★ (50) | In Derry |
| Spencer Deal Heating Services LLC | 4.0★ (2) | 7 mi |
| Valerio Air Systems Inc | 3.0★ (2) | 13 mi |
National price ranges in USD, not adjusted for Derry. 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 New Hampshire, furnace and heat pump calls peak in the coldest winter weeks and AC calls in summer heat waves. Spring and fall are the easiest times to book maintenance or a replacement.
We scored 603 Derry HVAC contractors on 8 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. Unknown factors are left out of the score, 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 Derry data |
|---|---|---|---|
| Reputation | 35% | Bayesian-adjusted Google star rating | Measured |
| Credentials | 15% | Active state license 0.6, bond 0.2, workers’ comp 0.2 | Not yet collected |
| Review volume | 10% | log10(reviews + 1) against the list maximum | Measured |
| Recency | 10% | Share of reviews from the last 12 months | Not yet collected |
| Availability | 10% | Weekly open hours, Saturday, Sunday, 24/7 or same-day | Measured |
| Trade focus | 10% | Google main category 1.0, business name 0.7, additional category 0.5 | Measured |
| Proximity | 5% | 1.0 when based in the city, falling to 0 at the trade’s radius | Measured |
| Completeness | 5% | Website, photos, description, hours, claimed profile (0.2 each) | Measured |