60 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Union: Level 9 Heating Cooling Plumbing, CR Score 65/100; 4.9★ from 1,254 Google reviews; open 24/7.
Best for emergencies (open 24/7): Lakebrink Heating & Air Conditioning, posts 24/7 hours; ranked #2 of 60.
Most-reviewed: The Appliance Guys, 3,464 Google reviews at 4.6★, the most of 60 ranked; ranked #42.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
60 Union HVAC contractors are ranked here by CR Score, from ten published factors. 15 are open 24/7, 31 open Saturdays and 24 open Sundays, based on posted hours. The median Google rating is 4.9★ across 60 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Level 9 Heating Cooling Plumbing | 65 | 4.9★ (1,254) | Washington, 6 mi away | 24/7 | Overall |
| 2 | Lakebrink Heating & Air Conditioning | 62 | 4.7★ (99) | Union | 24/7 | Emergencies |
| 3 | Menke Heating and Cooling | 61 | 5.0★ (99) | Union | 24/7 | — |
| 4 | Renaud Brothers Heating & Cooling | 60 | 5.0★ (609) | Wentzville, 22 mi away | 24/7 | — |
| 5 | Superior Service | 60 | 5.0★ (2,219) | Dardenne Prairie, 25 mi away | Sat · Sun · Evenings | — |
| 6 | Fresh Air Heating and Cooling | 60 | 4.9★ (1,784) | Chesterfield, 24 mi away | Sat · Sun · Evenings | — |
| 7 | Saylors Systems Heating and AC Repair | 59 | 5.0★ (174) | Eureka, 20 mi away | 24/7 | — |
| 8 | Brandt HVAC | 58 | 5.0★ (7) | Union | 24/7 | — |
| 9 | Crystal Heating & Cooling | 58 | 4.9★ (497) | Washington, 6 mi away | — | — |
| 10 | Future Aire | 58 | 4.7★ (320) | Eureka, 20 mi away | 24/7 | — |
Ordered by CR Score, a 0–100 score from ten published factors. Paid placement never changes the order.
Ranked #1 because of its Google rating and trade focus: 4.9★ from 1,254 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #2 because of its Google rating and trade focus: 4.7★ from 99 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #3 because of its Google rating and trade focus: 5.0★ from 99 Google reviews, listed on Google as “Air conditioning contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Wentzville, 22 mi away
Ranked #4 because of its Google rating and trade focus: 5.0★ from 609 Google reviews, listed on Google as “Air conditioning contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Dardenne Prairie, 25 mi away
Ranked #5 because of its Google rating and trade focus: 5.0★ from 2,219 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Chesterfield, 24 mi away
Ranked #6 because of its Google rating and trade focus: 4.9★ from 1,784 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Eureka, 20 mi away
Ranked #7 because of its Google rating and trade focus: 5.0★ from 174 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #8 because of its Google rating and trade focus: 5.0★ from 7 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Washington, 6 mi away
Ranked #9 because of its Google rating and trade focus: 4.9★ from 497 Google reviews, listed on Google as “Furnace repair service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Eureka, 20 mi away
Ranked #10 because of its Google rating and trade focus: 4.7★ from 320 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Sullivan, 19 mi away
Ranked #11 because of its Google rating and trade focus: 4.9★ from 308 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #12 because of its Google rating and trade focus: 4.7★ from 32 Google reviews, listed on Google as “Air conditioning contractor”.
Based on 7 of 10 factors; credentials, recency and availability not yet collected.
Based in Eureka, 20 mi away
Ranked #13 because of its Google rating and trade focus: 4.8★ from 104 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #14 because of its Google rating and trade focus: 4.9★ from 88 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #15 because of its Google rating and trade focus: 4.8★ from 91 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Washington, 8 mi away
Ranked #16 because of its Google rating and trade focus: 5.0★ from 9 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Wildwood, 8 mi away
Ranked #17 because of its Google rating and trade focus: 4.8★ from 19 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Pacific, 15 mi away
Ranked #18 because of its Google rating and trade focus: 4.6★ from 26 Google reviews, listed on Google as “Heating contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Saint Peters, 11 mi away
Ranked #19 because of its Google rating and trade focus: 5.0★ from 45 Google reviews, listed on Google as “Heating contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Wentzville, 22 mi away
Ranked #20 because of its Google rating and trade focus: 5.0★ from 31 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #21 because of its Google rating and trade focus: 5.0★ from 6 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Saint Peters, 23 mi away
Ranked #22 because of its Google rating and trade focus: 5.0★ from 25 Google reviews, listed on Google as “Air conditioning contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Pacific, 15 mi away
Ranked #23 because of its Google rating and trade focus: 3.9★ from 33 Google reviews, listed on Google as “Air conditioning contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Union
Ranked #24 because of its Google rating and trade focus: 4.8★ from 16 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Pacific, 15 mi away
Ranked #25 because of its Google rating and trade focus: 4.8★ from 186 Google reviews, listed on Google as “HVAC contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
#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 60 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 |
|---|---|---|
| Air Conditioner & Furnace Repair Derek's Heating, Cooling & Electrical LLC. | In Union | |
| Air Services Heating & Cooling | 18 mi | |
| Aire Serv of Eureka | 20 mi | |
| AVS Heating and Cooling | 4.2★ (5) | 22 mi |
| CHARMOR HVAC | 5.0★ (1) | 24 mi |
| Davidson Home Improvement LLC | 17 mi | |
| Doll Mechanical Services & Engineering | 5.0★ (5) | 13 mi |
| Doyle Patton Service | 24 mi | |
| Filla Heating and Cooling | In Union | |
| Gradel Heating & Cooling LLC | 5.0★ (3) | 10 mi |
| hth companies, inc. | 4.6★ (19) | In Union |
| Innovation Mechanical Inc. | In Union | |
| J.S Heat And Air Conditioning | 4.4★ (13) | 22 mi |
| Joseph's Heating and Air Conditioning | 23 mi | |
| LCS Plumbing & Electrical | 4.9★ (51) | In Union |
| Menke Heating and Cooling | In Union | |
| Mueller Air & Appliance | 24 mi | |
| One Cool Hot Chick HVAC & Home Repairs | In Union | |
| SERVPRO of Franklin County | 4.8★ (88) | In Union |
| Suermann Plumbing & Construction | 23 mi |
National price ranges in USD, not adjusted for Union. 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 |
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 60 Union 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 Union 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 |