21 AC Replacement Contractors in Longmont, CO
Top-Rated AC Replacement Contractors in Longmont
Prime Performance Mechanical
“5 of 6 displayed reviews carry 5-star ratings, with owners consistently noting the founder's hands-on involvement. Single negative feedback centered on…”
My Guy Heating and Air (Firestone)
“All six detailed reviews award 5 stars, with each reviewer voluntarily naming specific technicians, Bob, David, Park, Daniel, Bryan, Ivan, and Carlos, as…”
All AC Replacement Contractors (21 total)
BlueBird Windows & Doors
“673 reviews yield a 4.9 average rating. Named technicians appear across multiple five-star reviews: Irene and…”
Groulx Mechanical Heating & Cooling Inc.
“All five reviewers awarded five-star ratings, with each account mentioning specific team members by name.…”
KJ Thomas Mechanical
“All 252 reviews carry 5-star ratings, with customers consistently praising honest estimates, on-time…”
Longmont Water Heaters
“Six recent reviewers awarded 5-star ratings, with three specifically mentioning same-day or next-day response…”
Colorado's Finest Heating and Air Conditioning
“215 reviews yield a 4.9 average rating, with Jordan mentioned specifically across multiple five-star reviews…”
Streamline Plumbing, LLC
“149 of 150 reviewers award 5 stars, praising same-day service, flat hourly pricing, and technician…”
Your Comfort Heating & Cooling
“Every reviewer awarded a perfect 5-star rating, with Dean named directly in six of seven published…”
Bliss Water Heater & Boiler Repair Service
“All 72 reviews carry 5-star ratings, with customers frequently mentioning free troubleshooting, same-day…”
Stone Heating & Air
“Sixth-month review demonstrates consistent praise: all five-star ratings mention fair pricing and transparent…”
McColl Electrical Services, LLC
“Forty-nine reviews yield a 4.8-star average, with technicians Dominic and John appearing across most positive…”
Highland Heating & Air, Inc.
“5 of 7 reviewers assign 5-star ratings, with Chris, Scott, Jack, and Ashley named as individual technicians.…”
SAC Mechanical Heating & Air Conditioning
“Three reviews yield two five-star endorsements citing responsive same-day arrival, thorough furnace…”
Colorado Green Plumbing, Heating & Cooling
“All 30 reviews award 5 stars, with multiple reviewers specifically mentioning fair pricing, accurate…”
Maddison Mechanical, Inc
“Two positive reviews name specific technicians (Paul, Logan) praised for resolving complex equipment…”
BCIT Mechanical
“Three of five detailed reviews mention same-day or urgent same-week service response. All five-star reviews…”
Comfort Craft
“Five of six reviews award five stars, praising fair pricing and repairs that avoided expensive replacements.…”
Foundations Mechanical Services
“The sole verified reviewer awards 5 stars and specifically praises the contractor's punctuality and…”
AC Replacement Costs in Longmont
Replacement costs for aging systems in Longmont. If repair cost exceeds 50% of replacement, replacement is usually more economical.
| Service | Low | Average | High |
|---|---|---|---|
Central AC (3-ton, basic) | $6,160 | $8,960 | $12,320 |
Central AC (4-ton, mid-efficiency) | $8,400 | $11,760 | $15,680 |
Central AC (5-ton, high-efficiency) | $10,640 | $14,000 | $17,920 |
Full HVAC system (AC + furnace) | $12,981 | $15,042 | $15,792 |
Plus ductwork replacement If existing ducts are aged/leaking | $2,352 | $3,360 | $4,480 |
| Repair cost threshold | 50% rule: if repair > 50% of replacement, replace | ||
Prices reflect continental metro averages compiled from published industry cost guides, contractor surveys, and regional labor data. Last updated: April 2026.
AC Replacement in Longmont, CO: What to Expect
Longmont’s summers are warm and dry on the northern Front Range, and residents feel the effect of thin, high-altitude air that derates equipment 10–15% compared with sea-level specs. That altitude plus a heating-dominated load calculation means sizing errors become obvious quickly. Six contractors serve the area, averaging a 4.8 rating from 2,813 reviews, and many homeowners search for ac-replacement Longmont specialists who understand those quirks.
Local bids for AC replacement vary widely because final costs hinge on equipment choice, refrigerant type, ductwork repairs and labor; top-cost items typically include the condenser, any required line-set changes, and electrical upgrades. Colorado has no statewide HVAC license, so local municipal or county licensing and permits govern installations and inspections; homeowners should verify the specific local credentials and permit history for any bid they consider.
Customer highlights were not provided, so look instead for consistent reviewer themes: clear sizing explanations, documented high-altitude adjustments, transparent warranty terms and timely communication. Four of the six contractors advertise 24/7 availability, which shows service responsiveness matters here. Prioritize technicians who can demonstrate load calculations that account for thin air and cold-season heating interplay rather than offering one-size-fits-all recommendations.
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All HVAC Contractors in Longmont, CO
Complete directory of 71 contractors — browse alphabetically
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All HVAC Contractors in Longmont, CO
Complete directory of 71 contractors — browse alphabetically