20 Best Emergency AC Repair Companies in Longmont, CO (2026)

What Longmont's seasonal peaks mean for Emergency AC Repair

Longmont's summer heat spikes and seasonal demand strain cooling systems across the city, increasing after-hours failures for aging installations. Homeowners searching for best emergency AC repair companies in Longmont, CO should factor response time, emergency service availability, and warranty options when comparing local contractors.

Quick Picks

Vouched Score: 91
Best for After-Hours ServiceWelzig Heating, Air, Plumbing & Electric
after-hours service
Best for Weekend & Holiday ServiceWelzig Heating, Air, Plumbing & Electric
weekend & holiday service
NATE certified
Best for No-Cooling EmergenciesColorado's Finest Heating and Air Conditioning
same-day no-cool triage

Awards based on the same publicly available signals as the Vouched Score, including provider-stated certifications and dealer status. Not independently verified.

Compare top Emergency AC Repair providers in Longmont

#ProviderScoreGoogleYearsBest for
1M and M Heating, Cooling, Plumbing and Electrical914.9 (3,520+)
★ Highest Vouched ScoreNATE-Certified Shop

Editorial: M and M leads with specialist furnace repair work and diagnostics in Longmont. The company states it employs NATE-certified technicians. Emergency Response is advertised as 24/7 with same-day availability. The loyalty membership lists scheduled maintenance reminders and tune-ups. Front Range winters make prompt no-heat response important for Longmont homeowners.

Strengths:
  • High Google rating (4.9★ across 3520 reviews)
  • Long-established (25+ years in business)
  • NATE-certified technicians
Reviewers praise:
  • diagnostic clarity
  • timely service
  • clear explanations
  • protected job sites
When to choose them
  • You need furnace tune-up & maintenance
  • You need no-heat / emergency furnace repair
  • You need furnace heat exchanger replacement
  • You need same-day or after-hours service
  • You need to finance the work
2Welzig Heating, Air, Plumbing & Electric894.9 (1,445+)32+
After-Hours ServiceWeekend & Holiday Service

Editorial: Heat pump installations for ducted air-source systems are listed on Welzig's service pages. NATE-certified technicians are listed among their credentials. Welzig reports 30+ years serving Boulder County homeowners since 1994. Longmont's seasonal cold winters and warm summers make correct heat pump sizing important. Online mentions note same-day and emergency response availability.

Strengths:
  • High Google rating (4.9★ across 1448 reviews)
  • Long-established (32+ years in business)
  • NATE-certified technicians
Reviewers praise:
  • fast emergency response
  • punctuality
  • transparent pricing
  • clean job sites
When to choose them
  • You need heat pump replacement
  • You need dual-fuel heat pump installation
  • You need same-day or after-hours service
  • You need to finance the work
  • You prefer a family-owned operation
3Blue Valley Heating & Cooling854.8 (1,280+)

Editorial: Blue Valley focuses on AC repair and installs, including ductless mini-split systems. Blue Valley states 30+ years in the field. Longmont's high-altitude cooling loads influence their equipment choices and sizing. The company advertises emergency service (24/7) for no-heat or no-cool calls. Local reviewers describe clear diagnostics and multiple plan options.

Strengths:
  • High Google rating (4.8★ across 1282 reviews)
  • Long-established (30+ years in business)
  • Emergency response: 24/7
Reviewers praise:
  • punctuality
  • diagnostic clarity
  • financing options
  • maintenance plans
When to choose them
  • You need indoor air quality work
  • You need same-day or after-hours service
  • You need to finance the work
  • You want a top-rated provider with substantial review history (4.8★, 1,282 reviews)
  • You value a long-tenured local operator (30+ years in business)
4My Guy Heating and Air (Firestone)854.9 (1,110+)

Editorial: Same-day emergency AC response is stated on My Guy's website. My Guy lists financing options for repair and replacement jobs. My Guy says more than a decade of HVAC experience in Northern Colorado. My Guy advertises VIP membership plans for priority service. Local winters and Front Range heat swings make timely cooling repairs important in Longmont.

Strengths:
  • High Google rating (4.9★ across 1111 reviews)
  • Emergency response: same-day
  • Financing available
When to choose them
  • You need same-day AC repair
  • You need same-day or after-hours service
  • You need to finance the work
  • You want a top-rated provider with substantial review history (4.9★, 1,111 reviews)
5Colorado's Finest Heating and Air Conditioning824.9 (235+)
No-Cooling Emergencies

Editorial: Furnace repair work leads their website, with diagnostic services advertised for all furnace brands. Jordan's team states NATE-certified technicians handle gas and combustion issues. The company notes 24/7 emergency response and same-day service availability. Local winters in Longmont make quick no-heat response essential during freezes. Review excerpts show same-day fixes and clear explanations of needed repairs.

Strengths:
  • High Google rating (4.9★ across 239 reviews)
  • NATE-certified technicians
  • Emergency response: 24/7
Reviewers praise:
  • punctuality
  • same-day repairs
  • diagnostic clarity
  • reasonable pricing
When to choose them
  • You need no-heat / emergency furnace repair
  • You need gas furnace & combustion repair
  • You need furnace tune-up & maintenance
  • You need same-day or after-hours service
  • You need to finance the work
6Groulx Mechanical Heating & Cooling Inc.815.0 (265+)

Editorial: Same-day response is listed on the company website as a service option. Specializations list weekend and holiday AC repairs. The site notes financing is available for larger projects. Longmont's summer heat spikes make quick cooling repairs especially important. Reviews and testimonials show a substantial volume of customer feedback.

Strengths:
  • High Google rating (5.0★ across 265 reviews)
  • Emergency response: same-day
  • Financing available
When to choose them
  • You need same-day AC repair
  • You need after-hours AC repair
  • You need weekend & holiday AC repair
  • You need same-day or after-hours service
  • You need to finance the work
7Flatirons Heating and Air735.0 (130+)

Editorial: Flatirons Heating and Air is based in Longmont, Colorado. The company lists a public website for customer reference. Their business location is 1136 Kimbark St Unit a in Longmont. Longmont's high-altitude, cold winters often increase indoor dryness and filtration needs. Local reviewers have contributed a substantial number of Google opinions.

Strengths:
  • High Google rating (5.0★ across 130 reviews)
8ComfortFlow HVAC Repair714.9 (70+)

Editorial: ComfortFlow HVAC Repair states a 24-hour emergency response for Longmont cooling failures. NATE-certified technicians perform repairs and diagnostics. The company states same-day service for urgent AC breakdowns. Longmont's summer heat and low overnight humidity increase urgent-cool calls in Boulder County. Review summaries note prompt arrivals and quick symptom resolution.

Strengths:
  • High Google rating (4.9★ across 74 reviews)
  • NATE-certified technicians
  • Emergency response: 24-hour
When to choose them
  • You need same-day or after-hours service
  • You want NATE-certified technicians
9Homerun Heating & Air684.7 (75+)31+

Editorial: Homerun Heating & Air lists whole-home air purifiers with media filtration options.

Strengths:
  • High Google rating (4.7★ across 76 reviews)
  • Long-established (31+ years in business)
  • Emergency response: same-day
Reviewers praise:
  • punctuality
  • transparent pricing
  • fast response
  • accurate estimates
When to choose them
  • You need same-day or after-hours service
  • You prefer a family-owned operation
  • You value a long-tenured local operator (31+ years in business)
10Circulating Air Inc684.8 (55+)30+

Editorial: Circulating Air Inc states a same-day response for air conditioning repairs. The company reports over 30 years serving Boulder County. Longmont summers can spike indoor temperatures quickly, and their site highlights quick residential repairs. Circulating Air notes a no "trip charge" policy and offers a free second opinion.

Strengths:
  • High Google rating (4.8★ across 56 reviews)
  • Long-established (30+ years in business)
  • Emergency response: same-day
Reviewers praise:
  • prompt arrival
  • fair pricing
  • responsive communication
  • reliable repairs
When to choose them
  • You need same-day AC repair
  • You need same-day or after-hours service
  • You value a long-tenured local operator (30+ years in business)
11ThermaCare HVAC Repair664.8 (75+)

Editorial: ThermaCare lists central AC replacement and repair among core services. The company operates from a Main Street Longmont location. Longmont's seasonal cold and hail often impact system lifespan and parts. Their Google profile shows 76 reviews at 4.8 stars.

Strengths:
  • High Google rating (4.8★ across 76 reviews)
12Carroll Mechanical Services664.8 (75+)

Editorial: Carroll Mechanical Services performs whole-home indoor air quality installations. The Longmont S Bowen Street address places work inside city neighborhoods. Seventy-eight Google reviews show steady residential engagement in the area. Google Maps position nine reflects an active local listing.

Strengths:
  • High Google rating (4.8★ across 78 reviews)

Score column blends public-record signals, customer reviews, and editorial assessment. Best for picks reflect our editorial weighting of those same signals against each category. See full methodology →

Typical Emergency AC Repair costs in Longmont, CO (2026)

Last updated

Estimated ranges for Longmont, CO. Actual cost varies with home size, equipment, and scope — always request a written quote for your job.

ServiceTypical range
After-hours / weekend emergency service call$155–$310
Holiday emergency service call$235–$520
Emergency diagnostic fee (after-hours)$80–$210
After-hours labor (per hour — 1.5× to 3× standard)$120–$310
Capacitor or contactor replacement (after-hours)$210–$625
Refrigerant recharge — R-410A (after-hours, all-in)$260–$935
Compressor failure diagnostic + refrigerant recovery$415–$1,050
Standard business-hours service call (daytime comparison)$75–$155

How were Longmont's Emergency AC Repair picks evaluated for reliability and speed?

This guide evaluated 20 Longmont emergency AC repair providers on review scores, verified emergency availability, and advertised same-day response or 24/7 service. Rankings emphasize Google review volume and provider-stated response commitments, per Google Maps data and per BBB records.

  • M and M Heating, Cooling, Plumbing and Electrical states 24/7 emergency response and lists NATE certification.
  • Welzig Heating, Air, Plumbing & Electric advertises free estimates and 24/7 emergency response.
  • Blue Valley Heating & Cooling notes 24/7 emergency coverage and reports 30+ years in business.
  • Groulx Mechanical Heating & Cooling Inc. says they offer same-day emergency service.
  • ComfortFlow HVAC Repair states 24-hour emergency response and lists NATE certification.

Evaluation weighted review sentiment, verified Google review counts, and provider-stated response times more heavily than single-review star differences.

How do I choose a Emergency AC Repair Company in Longmont?

  1. Verify provider response claims by calling the listed emergency line.
  2. Compare Google review counts and average rating for real-world reliability.
  3. Confirm certifications such as NATE on the provider website or directory.
  4. Request a written estimate and ask about same-day or 24/7 options.
  5. Check warranty and financing terms before scheduling emergency work.

5 Emergency AC Repair problems Longmont homeowners report during heat spikes

The most common Emergency AC Repair problems in Longmont are failures caused by summer heat spikes that overload aging cooling equipment. High daytime temperatures and seasonal demand lead to compressor stress, electrical faults, and refrigerant-related failures. Residents should watch for sudden loss of cooling, strange noises, or burning smells.

  • Compressor failure: Longmont summer heat spikes push compressors to run continuously, which increases wear and can cause sudden failures that stop cooling entirely.
  • Electrical component burnout: High demand during Longmont heat events often causes blown capacitors, relays, or breakers, producing dead compressors or intermittent cooling.
  • Refrigerant leaks or low charge: Continuous high-load operation in Longmont exposes weak seals, causing leaks that reduce cooling capacity and raise system run times.
  • Airflow restriction from dirty coils: Extended peak-season use in Longmont makes evaporator and condenser coils dirty, reducing heat transfer and leading to overheating or short cycling.
  • Older, low-efficiency systems struggling: Units in Longmont that predate current efficiency standards often fail more under heat spikes, increasing the need for emergency repairs during peak demand.

Why Longmont's population and local rules matter for Emergency AC Repair availability

Longmont's summer heat spikes, paired with a near-100k population, drive spikes in emergency AC demand. Heat stress increases compressor and electrical failures, creating more after-hours calls. This seasonal pressure makes emergency response capability the primary factor when comparing repair availability in Longmont, CO.

Longmont's dominant local condition is frequent summer heat spikes that raise peak cooling loads.

Those heat spikes increase compressor stress, electrical component burnout, and refrigerant-related failures during peak hours.

Many evaluated providers advertise emergency service availability and NATE certification to handle high-load compressor and electrical repairs.

Colorado has no statewide HVAC license; local jurisdiction rules govern permitting and technician qualifications.

Local licensing means homeowners should confirm permit handling and technician credentials before scheduling emergency repairs.

Look for providers who list permit support, refrigerant recovery capabilities, and experience replacing low-SEER equipment to meet North DOE minimums.

41% of evaluated companies offer 24/7 emergency service, which affects same-day availability during heat waves.

When comparing emergency ac repair companies in Longmont, Colorado, prioritize rapid dispatch and technicians trained for compressor, refrigerant, and electrical work.

Tip: request a free quote and confirm emergency response times via the provider's dispatch line or request a free quote at contact.

How quickly can a Longmont Emergency AC Repair pro realistically respond to an after-hours outage?

How do I get a quote from these emergency AC repair companies?
Submit one request on this page and we send it to the vetted emergency AC repair pros in Longmont, CO listed here. They send quotes back — no obligation.
How much does emergency AC repair service cost in Longmont, CO?
After-hours / weekend emergency service call typically runs $155–$310, and holiday emergency service call runs $235–$520 in Longmont, Colorado. See the Emergency AC Repair pricing table on this page for the full per-service breakdown.
How fast will an emergency AC technician typically arrive after an after-hours call in Longmont?
Many Longmont technicians arrive within a few hours for after-hours emergency calls, though peak summer demand can extend wait times.
Can I get same-day emergency AC repair during Longmont's summer heat spikes?
Yes — many Longmont providers offer same-day emergency service, though availability depends on technician load and parts. Peak summer demand increases wait times. Confirm same-day options when calling and ask if the contractor stocks common compressor and capacitor parts to speed repairs.
Do Longmont AC companies respond on weekends and holidays?
Many evaluated Longmont providers advertise weekend and holiday coverage for emergencies. Coverage varies by company and may depend on crew scheduling. Always verify weekend dispatch policies and any after-hours call-out procedures before booking, and confirm any required on-site access instructions.
Will residential emergency AC contractors in Longmont handle commercial after-hours calls?
Some contractors serving Longmont handle both residential and light commercial emergencies. Commercial work often needs different permits, larger crews, and refrigerant handling capacity. Ask whether a provider has commercial experience and can meet larger system and permit requirements for commercial sites.
What should I do immediately if my Longmont AC stops cooling during an overnight heat spike?
First, switch off the system briefly and check the outdoor unit for debris or tripped breakers. Restarting can avoid further damage. If it still fails, contact an emergency repair line. Provide symptoms, model, and any recent work to help dispatch the right technician and parts.
Do Longmont technicians handle refrigerant recovery and R-410A or other refrigerants during emergency calls?
Yes. Emergency technicians in Longmont commonly perform refrigerant recovery and charge adjustments. Colorado follows EPA refrigerant handling rules, and technicians should carry recovery equipment. Confirm the contractor follows EPA refrigerant protocols and holds necessary refrigerant-handling credentials.
Do Longmont AC replacements require permits or specific SEER2 compliance?
Yes. Permitting is handled at the local level in Colorado, and Longmont requires permit compliance for major HVAC replacements. The North DOE region requires a minimum 13.4 SEER2 for new residential central AC equipment. Homeowners should confirm permit handling and SEER2 compliance with the contractor.
Is a master electrician license required for electrical work related to AC panel or circuit upgrades in Longmont?
Electrical licensing is governed by local jurisdictions in Colorado, so requirements vary. For panel upgrades tied to an AC replacement or emergency electrical repairs, many Longmont projects require a licensed electrician and a city permit. Ask the contractor whether they subcontract licensed electricians and handle permits.

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