131 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Groton: Kneeland heating & Cooling LLC, CR Score 64/100; 4.6★ from 169 Google reviews; open 24/7.
Best for emergencies (open 24/7): Connecticut HVAC Services llc, posts 24/7 hours; ranked #4 of 131.
Most-reviewed: South Shore Heating & Cooling Inc, 564 Google reviews at 4.9★, the most of 131 ranked; ranked #6.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
131 Groton HVAC contractors are ranked here by CR Score, from ten published factors. 20 are open 24/7, 36 open Saturdays and 28 open Sundays, based on posted hours. The median Google rating is 4.6★ across 131 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Kneeland heating & Cooling LLC | 64 | 4.6★ (169) | Groton | 24/7 | Overall |
| 2 | Densmore Oil Company | 61 | 4.9★ (283) | Groton | — | — |
| 3 | DDLC Energy | 61 | 4.7★ (422) | New London, 1 mi away | — | — |
| 4 | Connecticut HVAC Services llc | 61 | 4.6★ (107) | Guilford, 9 mi away | 24/7 | Emergencies |
| 5 | DTS Oil & Gas Service & Solutions LLC | 60 | 5.0★ (150) | Hebron, 22 mi away | 24/7 | — |
| 6 | South Shore Heating & Cooling Inc | 60 | 4.9★ (564) | Pawcatuck, 11 mi away | — | Most reviews |
| 7 | Duncklee Cooling & Heating Inc | 60 | 4.7★ (256) | Groton | — | — |
| 8 | Carnot Heating | 59 | 4.6★ (9) | Groton | 24/7 | — |
| 9 | HVAC Restorations LLC. | 59 | 5.0★ (33) | Norwich, 14 mi away | 24/7 | — |
| 10 | Scotti Mechanical Heating and Cooling | 58 | 4.6★ (35) | Waterford, 4 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 trade focus: 4.6★ from 169 Google reviews, listed on Google as “Heating contractor”.
Based in Groton
Ranked #2 because of its Google rating and trade focus: 4.9★ from 283 Google reviews, listed on Google as “HVAC contractor”.
Based in New London, 1 mi away
Ranked #3 because of its Google rating and trade focus: 4.7★ from 422 Google reviews, listed on Google as “Air conditioning contractor”.
Based in Guilford, 9 mi away
Ranked #4 because of its Google rating and trade focus: 4.6★ from 107 Google reviews, listed on Google as “Air conditioning contractor”.
Based in Hebron, 22 mi away
Ranked #5 because of its Google rating and trade focus: 5.0★ from 150 Google reviews, listed on Google as “HVAC contractor”.
Based in Pawcatuck, 11 mi away
Ranked #6 because of its Google rating and review volume: 4.9★ from 564 Google reviews, the most in Groton.
Based in Groton
Ranked #7 because of its Google rating and trade focus: 4.7★ from 256 Google reviews, listed on Google as “HVAC contractor”.
Based in Groton
Ranked #8 because of its Google rating and trade focus: 4.6★ from 9 Google reviews, listed on Google as “HVAC contractor”.
Based in Norwich, 14 mi away
Ranked #9 because of its Google rating and trade focus: 5.0★ from 33 Google reviews, listed on Google as “HVAC contractor”.
Based in Waterford, 4 mi away
Ranked #10 because of its Google rating and trade focus: 4.6★ from 35 Google reviews, listed on Google as “HVAC contractor”.
Based in Ledyard, 9 mi away
Ranked #11 because of its Google rating and trade focus: 4.9★ from 175 Google reviews, listed on Google as “HVAC contractor”.
Based in Ledyard, 10 mi away
Ranked #12 because of its Google rating and trade focus: 4.6★ from 28 Google reviews, listed on Google as “HVAC contractor”.
Based in Guilford, 20 mi away
Ranked #13 because of its Google rating and trade focus: 5.0★ from 467 Google reviews, listed on Google as “HVAC contractor”.
Based in Waterford, 2 mi away
Ranked #14 because of its Google rating and trade focus: 4.6★ from 118 Google reviews, listed on Google as “HVAC contractor”.
Based in East Haddam, 7 mi away
Ranked #15 because of its Google rating and trade focus: 5.0★ from 8 Google reviews, listed on Google as “HVAC contractor”.
Based in Charlestown, 19 mi away
Ranked #16 because of its Google rating and trade focus: 4.9★ from 280 Google reviews, listed on Google as “HVAC contractor”.
Based in Old Saybrook, 16 mi away
Ranked #17 because of its Google rating and trade focus: 4.4★ from 33 Google reviews, listed on Google as “HVAC contractor”.
Based in New London, 9 mi away
Ranked #18 because of its Google rating and trade focus: 5.0★ from 67 Google reviews, listed on Google as “HVAC contractor”.
Based in Conning Towers-Nautilus Park, 4 mi away
Ranked #19 because of its Google rating and trade focus: 4.9★ from 47 Google reviews, listed on Google as “HVAC contractor”.
Based in Groton
Ranked #20 because of its Google rating and trade focus: 5.0★ from 23 Google reviews, listed on Google as “HVAC contractor”.
Based in Pawcatuck, 13 mi away
Ranked #21 because of its Google rating and trade focus: 3.8★ from 32 Google reviews, listed on Google as “HVAC contractor”.
Based in New London, 2 mi away
Ranked #22 because of its Google rating and trade focus: 4.3★ from 48 Google reviews, listed on Google as “HVAC contractor”.
Based in Hebron, 22 mi away
Ranked #23 because of its Google rating and trade focus: 4.9★ from 264 Google reviews, listed on Google as “HVAC contractor”.
Based in Groton
Ranked #24 because of its Google rating and trade focus: 4.8★ from 21 Google reviews, listed on Google as “Heating contractor”.
Based in Westerly, 16 mi away
Ranked #25 because of its Google rating and trade focus: 5.0★ from 44 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 131 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/Z Corporation | 4.5★ (11) | In Groton |
| Action Air Inc. | 3.8★ (16) | 23 mi |
| American Air Mechanical LLC | 3.9★ (17) | 25 mi |
| ASI Assertive Solutions Inc | 4.0★ (4) | In Groton |
| Brayman Heating & Cooling, Inc | 3.0★ (2) | 17 mi |
| Chimney Works | 4.0★ (2) | In Groton |
| D J Mc Carthy Plumbing & Heating | 5.0★ (2) | 5 mi |
| Duncklee Cooling & Heating | 5.0★ (1) | In Groton |
| E W Leonard Inc | 4.7★ (6) | 22 mi |
| Genesis Heating And Cooling Co | In Groton | |
| H J Smith Inc | 5.0★ (12) | In Groton |
| Hank's Plumbing & Heating Services | 5.0★ (2) | 17 mi |
| Marlborough Heating & AC | 4.2★ (5) | 19 mi |
| MDK Mechancial LLC | 5.0★ (3) | 18 mi |
| Mohawk Northeast Inc | 4.6★ (31) | In Groton |
| Moonlight Plumbing LLC | 4.9★ (126) | In Groton |
| Plant Ahead Landscape | In Groton | |
| Rainville Plumbing & Heating | 5.0★ (4) | 16 mi |
| Robert Cassidy, Jr. Plumbing, and Heating Inc. | In Groton | |
| Suburban Plumbing & Heating | 4.0★ (4) | 2 mi |
National price ranges in USD, not adjusted for Groton. 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 Connecticut, Connecticut Department of Consumer Protection licenses Heating, piping, cooling and sheet metal licenses.
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
In Connecticut, 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 131 Groton 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 Groton 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 |