Top-Rated South Bay HVAC Companies
7 vetted contractors, thoroughly researched and ranked
Last Updated: September 1, 2026
Our Top Pick
Therma Tech Heating & Air Conditioning
License #913806 · Verified via CSLB
Honest, no-pressure diagnostics — multiple reviewers describe Therma Tech declining to upsell unnecessary full replacements that competitors had quoted.
Platform Scores
(225)
(694)
A+
NATE Certified
EPA 608 Certified
Carrier Authorized
Bryant Authorized
24/7 Emergency
Founded in 2008 (18 years), Therma Tech is a San Jose HVAC contractor specializing in residential heat pump conversions, AC and furnace repair, and high-efficiency system installations. Reviewers consistently highlight honest diagnostics without scare tactics, same-day response, and hands-on owner involvement from Henry Elia. Best for Silicon Valley homeowners wanting a straight-shooting, properly permitted installer for repairs or heat pump upgrades.
Essential Q&A
What makes them stand out?
Honest, no-pressure diagnostics — multiple reviewers describe Therma Tech declining to upsell unnecessary full replacements that competitors had quoted.
Who should hire them?
Silicon Valley homeowners wanting same-day repair or a properly permitted heat pump/high-efficiency upgrade from a NATE-certified, Carrier-authorized team that uses W-2 employees, not subcontractors.
Insider tip
Take the free diagnostic-with-repair and seasonal tune-up specials, and book ahead during heat waves — same-day slots fill fast and repeat customers report the most consistent results requesting a senior tech directly.
Platform Scores
(19)
(161)
A+
16 yrs
NATE Certified
Carrier Authorized
24/7 Emergency
44 years in business since 1981, specializing in Carrier HVAC installation, repair, and heat pump systems. Diamond Certified for 16 consecutive years with 286 verified customer surveys averaging 4.7 stars, known for owner involvement, honest pricing, and exceptional follow-up communication. Best for homeowners seeking a family-owned contractor with strong warranties and a proven track record of quality workmanship.
Essential Q&A
What makes them stand out?
Owner Ricardo Valderrama personally oversees jobs and is known for going above and beyond on warranty support, even helping with manufacturer warranties on systems he didn't install.
Who should hire them?
Homeowners who value quality workmanship over lowest price, want a family-owned contractor with decades of experience, and appreciate owner involvement and strong warranty backing.
Insider tip
Request Ricardo to personally assess your project—reviews consistently praise his technical knowledge, honest recommendations, and hands-on approach to ensuring installations are done right the first time.
Platform Scores
(225)
(248)
A+
21 yrs
84%
NATE Certified
Diamond Certified
BPI Building Analyst Certified
Lennox (Centurion Outstanding Dealer) Authorized
Mitsubishi Electric (Diamond Contractor) Authorized
64 years in business since 1962, specializing in residential and light commercial HVAC, electrical, and solar services. Distinguished by 21 consecutive years of Diamond Certification with 455 verified customer surveys and NATE-certified technicians with in-house training. Best for homeowners seeking a well-established, family-owned contractor with a proven track record and 100% satisfaction guarantee.
Essential Q&A
What makes them stand out?
21 consecutive years of Diamond Certification with 455 verified telephone surveys, combined with 64 years of family ownership and NATE-certified technicians trained through an in-house certification program.
Who should hire them?
Homeowners in Silicon Valley and the Peninsula who value an established, highly-credentialed contractor with verified customer satisfaction over the lowest price, particularly for complex projects or older homes.
Insider tip
Mention 'website offer' when scheduling for $100 off new furnace or AC installation, and ask about their price-match guarantee on maintenance services to maximize value.
Platform Scores
(423)
(214)
A+
5 yrs
NATE Certified Technicians
Bryant Certified Ductless Pro
Diamond Certified
Bryant Authorized
Mitsubishi Authorized
24/7 Emergency
Family-owned HVAC contractor serving Santa Clara County since 2014, specializing in residential and light commercial heating/cooling systems. Diamond Certified for 5 consecutive years with 109 verified customer surveys averaging 4.8 stars, known for technicians who explain work thoroughly and provide prompt, professional service. Best for homeowners seeking a reliable, locally-owned company with strong accountability and maintenance programs.
Essential Q&A
What makes them stand out?
Diamond Certified for 5 consecutive years with owner Joey Mangano personally involved in operations, offering a Care Club maintenance program with priority service and discounts for members.
Who should hire them?
Homeowners in Santa Clara County who value detailed explanations, want a family-owned company with strong accountability, and appreciate ongoing maintenance relationships over one-time transactions.
Insider tip
Join the Care Club maintenance program for priority scheduling, no overtime charges, and 20% off repairs—reviews consistently praise their proactive communication including pre-appointment texts with technician photos.
Platform Scores
(209)
(3)
N/A
24/7 Emergency
In business since 2007, this family-owned HVAC contractor specializes in residential heating, cooling, and duct cleaning services across Silicon Valley. Reviews consistently praise owner Sal's rapid response times, honest pricing without upselling, and professional workmanship with same-day service availability. Best for homeowners seeking affordable, no-pressure HVAC repairs and installations with personalized service from owners who answer every call.
Essential Q&A
What makes them stand out?
Owner-operated family business where Sal Sr. or Regina personally answer every call, providing rapid same-day response and honest, no-pressure pricing that reviewers frequently compare favorably to competitors charging significantly more.
Who should hire them?
Homeowners who value personal service, transparent pricing, and fast response times for residential HVAC repairs, maintenance, and installations in the South Bay area.
Insider tip
Call directly rather than using online forms - the owners answer personally and can often schedule same-day appointments, even on weekends; multiple reviewers noted Sal responded within 2 minutes of their initial request.
Platform Scores
(1,260)
(412)
N/A
Bryant Authorized
24/7 Emergency
Licensed since 2019 (operating as GDM Group, dba TRIO Heating Air Plumbing & Electrical) after rebranding from Pacific Air USA, this San Jose-based contractor holds an unusually broad B/C-10/C-20/C-36 license and specializes in heat-pump conversions, gas-to-electric electrification, installs, and repairs across the greater Bay Area. Reviews are strongly positive on communication, on-time arrival, no-pressure options-based selling, and transparent flat ('Set-In-Stone') pricing, with the multi-trade license letting them self-perform the electrical and plumbing that conversions require rather than subbing it out. Best for homeowners doing heat-pump/electrification work or wanting fast, communicative service who value upfront flat quotes.
Essential Q&A
What makes them stand out?
A rare four-classification license (General Building, Electrical, HVAC, Plumbing) lets them self-perform the panel work and plumbing that heat-pump and electrification conversions require, paired with standout communication and no-pressure, options-based selling.
Who should hire them?
Homeowners doing heat-pump or gas-to-electric conversions, or anyone wanting fast, well-communicated HVAC service who values transparent flat-rate quotes over the lowest possible bid.
Insider tip
Get the written 'Set-In-Stone' flat quote before work starts, and for installs confirm the permit is pulled and the city inspection passes — given a documented pre-rebrand code/callback issue, insist on the post-install inspection and ask for a specific well-reviewed technician by name.
Platform Scores
(312)
(167)
A+
87%
NATE Certified
Carrier Authorized
Goodman Authorized
In business since 2001, Sandium is an engineering-led HVAC contractor specializing in whole-home system design, heat-pump conversions, and energy-efficiency retrofits across Silicon Valley. Reviewers consistently praise thorough assessments, knowledgeable and tidy technicians, and competitive pricing backed by strong rebate expertise, though a recurring theme is slow after-sale warranty and repair turnaround when problems arise. Best for homeowners planning a new installation or electrification upgrade who value design rigor and rebate help over emergency-repair speed or the lowest bid.
Essential Q&A
What makes them stand out?
An engineering-first, whole-home design approach led by an engineer-owner, which separates them from install-only competitors who skip load calculations and root-cause assessment.
Who should hire them?
Homeowners planning a new system, heat-pump conversion, or whole-home comfort/efficiency upgrade who value design rigor and rebate guidance over rock-bottom pricing or fast emergency repair.
Insider tip
Get on their schedule early and expect a deposit, since they book out; lean on their Energy Upgrade California and PG&E rebate expertise on new installs, and confirm warranty/repair turnaround expectations up front because after-sale support is their weakest area.