Top commercial HVAC contractors in Houston, ranked by ChatGPT answers

Places ChatGPT showed

• Kilgore Industries · 4.3★ · Mechanical contractor
• Custom Air Products & Services, Inc. · 4.9★ · local_business
• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• Hunton Services · HVAC contractor
• RDI Mechanical · 4.7★ · Mechanical contractor
• Custom Air Products & Services Inc · 5.0★ · Air conditioning contractor
• The Way Companies · 4.9★ · HVAC contractor
• Environmental Air Systems Inc · 5.0★ · HVAC contractor

For commercial HVAC in Houston, I’d look first at contractors with substantial commercial/industrial experience rather than firms that primarily serve homeowners. Based on current Houston-area listings and contractor information, these are worth putting on your bid list:

• Kilgore Industries — A strong fit for large commercial/industrial projects, especially when HVAC is part of a broader mechanical, plumbing, or electrical scope. It also has 24/7 service and maintenance capabilities.
• Custom Air Products & Services, Inc. — Particularly interesting for industrial facilities, custom HVAC equipment, retrofits, chillers/AHUs, and specialized or hazardous-location applications.
• Gray Mechanical Contractors, LLC — Commercial mechanical contractor with capabilities including chillers, cooling towers, building automation, HVAC and plumbing, plus preventive maintenance.
• Hunton Services — Geared toward large facilities, industrial sites, healthcare/labs and campuses, with an emphasis on keeping mission-critical facilities operating.
• RDI Mechanical — Good candidate for commercial construction, renovations and mechanical/HVAC projects, with experience cited across data centers, healthcare, education, government, retail and industrial facilities.
• Custom Air Products & Services Inc — Another option if you need engineered/custom HVAC manufacturing and installation, rather than simply service and repair.
• The Way Companies — Worth considering for commercial/industrial HVACR, process cooling and building controls, particularly manufacturing or petrochemical-type environments.
• Environmental Air Systems Inc — Houston-area contractor established in 1982, with commercial HVAC/R, controls, installation, repair and air-quality capabilities.

How I'd narrow it down

If you need...	Contractors to investigate
Large commercial construction / MEP	Kilgore, RDI, Gray Mechanical
Industrial/process HVAC	Custom Air Products, The Way Companies, Hunton
Chillers/AHUs/custom equipment	Custom Air Products, Gray Mechanical
Ongoing maintenance & emergency service	Kilgore, Hunton, Gray Mechanical
Healthcare / campus facilities	RDI, Hunton, Kilgore
Smaller commercial building / straightforward HVAC	Environmental Air Systems, Traylor Mechanical

For example, Traylor Mechanical says it has 20+ years of experience and handles commercial HVAC installation, RTUs, split systems, chillers, preventive maintenance and 24/7 emergency response.

I wouldn't treat online star ratings as a definitive "best" ranking—commercial HVAC quality depends heavily on the type and size of your facility.

If you tell me what kind of building you have (office, warehouse, restaurant, apartment, medical, industrial, etc.), approximate square footage, and whether this is a new installation, replacement, or maintenance contract, I can narrow this to 3–5 Houston contractors that fit the job and compare their specialties, service areas, reviews, and contact information.

Places ChatGPT showed

• Kilgore Industries · 4.3★ · Mechanical contractor
• Custom Air Products & Services, Inc. · 4.9★ · local_business
• TDIndustries, Inc. · 4.2★ · Contractor
• Hunton Group · 4.5★ · HVAC contractor
• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• RDI Mechanical · 4.7★ · Mechanical contractor
• Hunton Services · 4.0★ · HVAC contractor
• Vista Air Services · 5.0★ · HVAC contractor
• Custom Air Products & Services Inc · 5.0★ · Air conditioning contractor
• Comflow Mechanical Services · 5.0★ · HVAC contractor
• Facilities Mechanical · 4.6★ · Contractor
• Premium HVAC Mechanical Services · 5.0★ · Air conditioning contractor
• The Way Companies · 4.9★ · HVAC contractor

For Houston office buildings and light-industrial facilities, I’d build the bid list around contractors with demonstrated commercial/industrial work rather than residential HVAC companies that also take commercial calls.

Houston contractors worth putting on an RFP list

• Kilgore Industries — Broad commercial/industrial mechanical contractor with HVAC, ductwork, industrial mechanical systems, fabrication, and a service arm offering planned maintenance and emergency response. A strong fit when HVAC is part of a larger MEP project.
• Custom Air Products & Services, Inc. — Particularly relevant for industrial facilities or technically complex HVAC. It designs, fabricates, installs, and services commercial/industrial HVAC equipment, including custom air-handling equipment and specialized applications.
• TDIndustries, Inc. — Large commercial mechanical/facilities contractor with capabilities spanning HVAC construction, service, maintenance, retrofits, and facility support. Its Houston operation has experience on major commercial buildings.
• Hunton Group — Worth considering for larger office buildings and sophisticated building systems, particularly where Trane equipment, controls/BAS, energy management, and ongoing service are important.
• Gray Mechanical Contractors, LLC — Houston commercial mechanical contractor with HVAC/plumbing construction, facility service, preventive maintenance, and building-automation capabilities.
• RDI Mechanical — Greater Houston commercial/industrial contractor covering service, maintenance, replacements, renovations, and new construction. Its stated markets include commercial, industrial, healthcare, education, and data centers.
• Hunton Services — Particularly interesting for facilities with industrial/process equipment in addition to conventional HVAC; it has an industrial plant services group and engineered/fabricated HVAC products.
• Vista Air Services — More focused on commercial/industrial HVAC service and maintenance, including preventive-maintenance programs and industrial process cooling.

For smaller light-industrial / office properties

If you're talking about, say, 10,000–100,000 sq. ft. offices, warehouses, flex buildings, or light-manufacturing facilities, I'd also look at:

• Custom Air Products & Services Inc
• Comflow Mechanical Services
• Facilities Mechanical
• Premium HVAC Mechanical Services
• The Way Companies

Several Houston contractors specifically advertise office/warehouse/light-industrial work. For example, Velocity Air says it handles office buildings, warehouses, distribution centers and light industrial facilities, while SAGE Air advertises commercial/light-industrial RTUs, VRF, cooling towers, boilers, retrofits and maintenance agreements.

How I'd narrow the field

For an office-heavy portfolio, I'd emphasize:

1. BAS/building controls capability
2. VAV and AHU experience
3. Preventive-maintenance programs
4. Tenant comfort/after-hours response
5. Energy audits and retrofit capability

For light industrial, I'd put more weight on:

1. RTU/AHU and makeup-air experience
2. High-volume ventilation
3. Process/industrial cooling experience
4. Crane/equipment replacement capability
5. 24/7 emergency response
6. Experience working around active manufacturing/warehouse operations

One particularly useful distinction is service contractor vs. mechanical construction contractor. If you're replacing equipment or doing a major retrofit, I'd want at least one large mechanical contractor and one specialized service contractor bidding the work rather than treating all HVAC firms as interchangeable.

If you tell me the approximate building size, type of HVAC equipment (RTUs, chillers, VRF, etc.), and whether you're looking for ongoing maintenance or a replacement/project, I can narrow this to a 5-company Houston shortlist with relevant experience, licensing, service area, and contact information.

Places ChatGPT showed

• Custom Air Products & Services, Inc. · 4.9★ · local_business
• G & W Service Company Inc · 4.9★ · Air conditioning repair service
• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• Kilgore Industries · 4.3★ · Mechanical contractor
• Hunton Services · HVAC contractor
• Graco Mechanical · Plumbing
• Vista Air Services · 5.0★ · HVAC contractor

If you need commercial rooftop units (RTUs) plus boiler systems, I’d focus on contractors with demonstrated experience across both unitary HVAC and hydronic/mechanical systems—not just companies that primarily do rooftop AC.

A Houston shortlist worth getting bids from:

• Custom Air Products & Services, Inc. — Particularly relevant for commercial/industrial facilities, RTU change-outs, boiler work, retrofits, and custom mechanical systems. Their published scope specifically includes boilers and rooftop package units.
• G & W Service Company Inc — Full commercial HVAC service including rooftop units, boilers, controls, chillers and air handlers. Useful if you want one contractor for ongoing service as well as repairs.
• Gray Mechanical Contractors, LLC — Commercial mechanical contractor with experience servicing RTUs, chillers, cooling towers, AHUs, VRF and other larger HVAC systems.
• Kilgore Industries — More oriented toward larger commercial/industrial projects, with HVAC, mechanical construction, piping and fabrication capabilities; its service operation handles RTUs, chillers and cooling towers.
• Hunton Services — A good candidate for complex commercial HVAC/mechanical plants, including controls and boiler-related work.
• Graco Mechanical — Broad commercial mechanical scope covering boilers, burners, chillers, AHUs, RTUs, pumps, VFDs and controls.
• Vista Air Services — Commercial/industrial contractor with RTU/AHU installation, rigging, piping/pumps and BAS integration.

For RTU-heavy work, Trane is also a significant local option: Trane has a Houston commercial sales office and local contractor network. Its Houston operation specifically supports commercial rooftop units and building controls.

How I'd narrow the bids

For a facility with both RTUs and boilers, ask each contractor to provide:

1. Specific RTU brands they are factory-trained/certified to service.
2. Boiler experience by fuel type, capacity and burner manufacturer.
3. Examples of comparable Houston-area facilities they've maintained.
4. Whether they perform combustion analysis, boiler-water treatment coordination and burner tuning in-house.
5. RTU replacement capabilities, including crane/rigging, curb adapters and controls integration.
6. A preventive-maintenance proposal rather than just an hourly service rate.
7. 24/7 emergency response and guaranteed response times.
8. References for projects involving both rooftop equipment and boiler plants.

One particularly useful distinction: if this is a large office, hospital, school, industrial facility or multi-building campus, I'd put more weight on the mechanical/boiler capabilities of companies such as CAPS, Hunton, Kilgore, Gray and Graco. If it's a smaller commercial building with packaged RTUs and a relatively simple boiler, a more service-oriented contractor may be sufficient.

If you tell me the building type, approximate square footage, number/tonnage of RTUs, and boiler size (if known), I can narrow this to a more targeted Houston shortlist and compare their capabilities.

Places ChatGPT showed

• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• Comflow Mechanical Services · 5.0★ · HVAC contractor
• Neva Corporation · 2.6★ · Air conditioning contractor
• OnPoint Mechanical LLC · 1.0★ · Mechanical contractor
• Halco Mechanical · 3.6★ · Mechanical contractor
• Vista Air Services · 5.0★ · HVAC contractor
• Traylor Mechanical · 5.0★ · General contractor
• K&R Mechanical Services · 4.4★ · HVAC contractor
• Archer Refrigeration LLC · 5.0★ · HVAC contractor
• Refrigeration Air Maintenance, LLC · 5.0★ · HVAC contractor
• ACF Mechanical · 5.0★ · HVAC contractor

Yes. I found several Houston-area contractors that explicitly advertise 24/7 emergency commercial HVAC service:

• Gray Mechanical Contractors, LLC — Commercial/industrial HVAC and mechanical contractor; advertises 24/7 emergency mechanical service, 365 days a year.
• Comflow Mechanical Services — Commercial HVAC and refrigeration; listed as available 24/7 for scheduled and emergency service.
• Neva Corporation — Specifically focused on commercial/industrial HVAC and refrigeration. It says it maintains technicians on call 24/7 for Houston businesses and industries.
• OnPoint Mechanical — Commercial mechanical contractor offering 24/7/365 emergency service and advertising a four-hour emergency response-time guarantee.
• Halco Mechanical — Full-service commercial mechanical/HVAC contractor with 24/7 emergency dispatch. Emergency: 713-824-7308.
• Vista Air Services — Commercial/industrial HVAC, including medical, government, industrial and large-facility work; advertises 24/7 mission-critical emergency service.
• Traylor Mechanical — Commercial HVAC contractor serving schools, government facilities and commercial buildings; advertises 24/7 emergency response.
• K&R Mechanical Services — Commercial HVAC/mechanical services with 24/7 availability.
• Archer Refrigeration LLC — Commercial HVAC/refrigeration and advertises 24/7 emergency coverage.
• Refrigeration Air Maintenance, LLC — Commercial HVAC/refrigeration contractor with 24/7 on-call emergency support.
• ACF Mechanical — Commercial HVAC/R and industrial refrigeration; advertises 24/7 emergency service.

A couple of important distinctions

If this is for a large commercial facility, industrial plant, chiller, or mission-critical building, I'd focus first on Neva, OnPoint, Halco, Vista Air, or Traylor because their published service descriptions specifically emphasize commercial/industrial facilities rather than primarily residential HVAC.

If you tell me your Houston ZIP code and the type of facility (office, restaurant, warehouse, apartment complex, medical, industrial, etc.), I can narrow this to 3–5 contractors that actually serve that area, including phone numbers, licenses, and emergency-response details.

Places ChatGPT showed

• Custom Air Products & Services Inc · 5.0★ · Air conditioning contractor

If you mean commercial HVAC work inside Houston city limits (office buildings, retail, restaurants, warehouses, multifamily, industrial, etc.), I’d look less at “best rated” lists and more at contractors with commercial focus, service capacity, licensed technicians, preventive maintenance programs, and experience with larger equipment (RTUs, chillers, BAS controls, VRF, make-up air, etc.). Houston has many residential HVAC companies that also say “commercial,” but the firms below are more aligned with commercial facilities.

★ 5.0 · Air conditioning contractor · Open

[Directions](https://www.google.com/maps/dir/?api=1&destination=Custom%20Air%20Products%20%26%20Services%2C%20Inc.%2C35%20Southbelt%20Industrial%20Dr%2C%20Houston%2C%20TX%2077047%2C%20United%20States) [Website](http://customairproducts.com/?utm_source=chatgpt.com) [Call](tel:+1 713-460-9009)

Vista Air Services

• Strong fit for: institutional, industrial, and commercial facilities needing ongoing service.
• Focuses on commercial/industrial HVAC infrastructure, including service, repair, and preventive maintenance.

Gray Mechanical Contractors, LLC

• Strong fit for: institutional, industrial, and commercial facilities needing ongoing service.
• Focuses on commercial/industrial HVAC infrastructure, including service, repair, and preventive maintenance.

The Way Companies

★ 4.8 · HVAC contractor · Open

[Directions](https://www.google.com/maps/dir/?api=1&destination=Gray%20Mechanical%20Contractors%2C%20LLC%2C15534%20W%20Hardy%20Rd%20%23100%2C%20Houston%2C%20TX%2077060%2C%20United%20States) [Website](http://www.graymechanical.com/?utm_source=chatgpt.com) [Call](tel:+1 281-820-2200)

Comflow Mechanical Services

The Way Companies

K&R Mechanical Services

• Strong fit for: commercial HVACR service, emergency response, facility support.
• Commercial/industrial HVACR provider with Houston operations and around-the-clock service listings.

Comflow Mechanical Services

★ 5.0 · HVAC contractor · Open

[Directions](https://www.google.com/maps/dir/?api=1&destination=Comflow%20Mechanical%20Services%2C6411%20Lawford%20Ln%2C%20Houston%2C%20TX%2077040%2C%20United%20States) [Website](http://www.comflowco.com/?utm_source=chatgpt.com) [Call](tel:+1 713-686-3600)

• Edco Air — listed among BBB-accredited commercial HVAC contractors in Houston.
• Hage Energy — listed as a commercial HVAC contractor serving Houston.
• Bayou City Aire, LLC — listed as a Houston-area commercial HVAC contractor.

K&R Mechanical Services

★ 4.4 · HVAC contractor · Open

[Directions](https://www.google.com/maps/dir/?api=1&destination=K%26R%20Mechanical%20Services%2C12634%20Haynes%20Rd%2C%20Houston%2C%20TX%2077066%2C%20United%20States) [Website](https://krmechanicalsvcs.com/?utm_source=chatgpt.com) [Call](tel:+1 281-408-9414)

• Strong fit for: commercial HVAC, controls, refrigeration, plumbing, and custom sheet metal work.
• A potential fit for facilities that want one mechanical contractor covering multiple systems.

Other Houston-area firms that appear in commercial HVAC listings

These may be worth bidding depending on project size and scope:

• Edco Air — listed among BBB-accredited commercial HVAC contractors in Houston.
• Hage Energy — listed as a commercial HVAC contractor serving Houston.
• Bayou City Aire, LLC — listed as a Houston-area commercial HVAC contractor.

How I’d narrow it down

For a large commercial building or mission-critical site, I’d typically request bids from:

1. Custom Air Products & Services
2. Vista Air Services
3. Gray Mechanical
4. The Way Companies

For a small-to-mid-size business (restaurant, retail, office, small warehouse), I’d also include:

• Comflow Mechanical
• K&R Mechanical
• Bayou City Aire

Before hiring, ask each contractor:

• Do you have a TACLA commercial HVAC license?
• How many commercial service technicians are assigned locally?
• Do you offer preventive maintenance agreements (PMAs)?
• What brands and equipment types do you regularly service (Trane, Carrier, York, Daikin, Lennox, chillers, BAS)?
• Can you provide recent references for buildings similar to yours?

If you tell me the building type (office, retail, restaurant, warehouse, apartment, industrial), approximate square footage, and whether this is repair vs. replacement vs. maintenance, I can narrow the list further.

Places ChatGPT showed

• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• Hunton Services · HVAC contractor
• RDI Mechanical · 4.7★ · Mechanical contractor
• Custom Air Products & Services, Inc. · 4.9★ · local_business
• Kilgore Industries · 4.3★ · Mechanical contractor
• K&R Mechanical Services · 4.4★ · HVAC contractor

Yes. If by “wider Houston metro” you mean contractors that explicitly cover suburbs and outlying communities—not just central Houston—there are several commercial-focused options.

• Gray Mechanical Contractors, LLC — Commercial/industrial HVAC and mechanical contractor. Its stated coverage includes Katy, Sugar Land, Pearland, Conroe, Cypress, Tomball, The Woodlands, Pasadena, Humble, Deer Park, and other Greater Houston communities.
• Hunton Services — Commercial/industrial HVAC and mechanical services, particularly suited to larger facilities, industrial sites, healthcare, labs, and campuses.
• RDI Mechanical — Based in Tomball and focused on commercial HVAC/mechanical construction, renovations, service, and maintenance throughout Greater Houston.
• Custom Air Products & Services, Inc. — Commercial/industrial HVAC, including custom equipment fabrication, installation, retrofits, maintenance, and specialized industrial applications.
• Kilgore Industries — Larger commercial/industrial MEP contractor handling HVAC, mechanical systems, ductwork, and related trades, with a Houston-area operation.
• K&R Mechanical Services — Commercial HVAC, refrigeration, controls/building automation, ductwork, installation, repair, and maintenance.
• OnPoint Mechanical — Explicitly lists Katy, Sugar Land, The Woodlands, Pearland, Pasadena, Baytown, and Conroe in its Greater Houston service area and handles commercial HVAC, chillers, cooling towers, VRF, and building automation.
• Aether HVAC — Commercial-construction oriented; specifically lists Katy, Sugar Land, Richmond, Missouri City, Pearland, Cypress, The Woodlands, Conroe, and surrounding counties.
• Texas Precise Mechanical — Commercial HVAC/refrigeration with a particularly broad stated footprint: Katy, Sugar Land, Richmond, Cypress, The Woodlands, Pearland, Pasadena, and Baytown.
• NexAir Solutions — Commercial/industrial HVAC serving Houston plus Sugar Land, Missouri City, Pearland, Katy, Richmond, Rosenberg, Cypress, Spring, The Woodlands, Tomball, Stafford, Pasadena, and others.

Particularly broad coverage

If your concern is one contractor being able to service locations scattered around the metro, rather than having to find separate contractors for north, west, south and east Houston, the stated coverage of Gray Mechanical, OnPoint Mechanical, Texas Precise Mechanical, and NexAir Solutions is worth looking at. Their published service areas span multiple sides of the metro.

For a large commercial/industrial facility or multi-site portfolio, I'd also look at Hunton, Kilgore, RDI, and Custom Air Products & Services, since their capabilities go beyond basic rooftop-unit repair into larger mechanical systems, construction, controls, industrial work, or engineered equipment.

If you tell me whether you're looking for office/retail, warehouse, multifamily, healthcare, restaurant, or industrial HVAC, I can narrow this to contractors whose published capabilities and geographic coverage match that type of property.

Places ChatGPT showed

• Vista Air Services · 5.0★ · HVAC contractor
• Hunton Services · HVAC contractor
• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• RDI Mechanical · 4.7★ · Mechanical contractor
• Premium HVAC Mechanical Services · 5.0★ · Air conditioning contractor
• Comflow Mechanical Services · 5.0★ · HVAC contractor
• Hunton Services · 4.0★ · HVAC contractor

For a commercial HVAC preventive maintenance (PM) program in Houston, the “best” fit depends heavily on your building type (office, industrial, healthcare, retail, data center, multifamily, etc.), equipment (RTUs, chillers, VRF, BAS), and how much reporting/control you need. I would compare contractors on maintenance depth, documentation, response structure, and commercial experience rather than just price.

Here are several Houston-area contractors with notable commercial PM offerings:

Contractor	Best fit	Preventive maintenance strengths
Vista Air Services	Industrial, institutional, large commercial facilities	Offers preventive maintenance agreements with scheduled inspections, coil cleaning, filter replacement, refrigerant checks, belt/motor inspections, and system documentation. It also highlights 24/7 emergency service and long-term commercial experience.
Hunton Services	Large facilities, campuses, healthcare, industrial plants	Focuses on planned/outcome-based maintenance, mechanical systems, controls, and reliability programs aimed at reducing downtime and operating costs.
Gray Mechanical Contractors, LLC	Commercial owners needing a full mechanical contractor	Provides commercial HVAC service capabilities including preventative maintenance and planned programs.
RDI Mechanical	Commercial/industrial owners, healthcare, education, data centers	Promotes preventive maintenance agreements designed around reducing breakdowns, managing energy costs, and extending equipment life.
Premium HVAC Mechanical Services	Businesses wanting a structured PM agreement with emergency support	Advertises scheduled inspections, preventive diagnostics, priority service, and emergency response options.
Comflow Mechanical Services	Facilities needing ongoing service + maintenance	Offers commercial HVAC maintenance agreements with scheduled quarterly, annual, or customized programs.
Hunton Services	Larger mechanical systems and facility management	Emphasizes preventive, planned, and outcome-based maintenance programs.

What I would look for in a strong Houston PM agreement

A good commercial PM contract should usually include:

• Quarterly or monthly inspections (not just annual tune-ups)
• Equipment inventory with model/serial numbers
• Refrigerant circuit checks and leak documentation
• Coil cleaning and condenser maintenance (important in Houston’s heat/humidity)
• Electrical testing (amp draws, capacitors, safeties, connections)
• Belt, bearing, motor, and fan inspections
• Condensate drain and humidity-control checks
• Filter management
• BAS/controls review if applicable
• Digital service reports with photos and measured readings
• Priority response terms during summer peaks
• Clear exclusions (parts, refrigerant, after-hours charges, etc.)

Several contractors advertise these types of structured programs. For example, Trane offers customizable commercial service agreements with preventive maintenance, diagnostics, refrigerant tracking, energy assessments, and controls support.

My shortlist by building type

• High-rise office / campus / healthcare: Hunton Services, Vista Air Services, RDI Mechanical
• Warehouse / industrial: Vista Air Services, Gray Mechanical, RDI Mechanical
• Retail / restaurants / smaller commercial: Premium HVAC Mechanical Services, Comflow Mechanical Services
• Owner-managed buildings wanting detailed reporting: Ask for a proposal that includes asset lists, inspection checklists, photos, and trend reports before signing

If you tell me your building type, square footage, number/type of HVAC units, and whether you need 24/7 response, I can narrow this to the most suitable Houston contractors and what a reasonable PM scope should look like.

Places ChatGPT showed

• Coopwood's Air Conditioning, Inc. · 5.0★ · Air conditioning contractor
• Vista Air Services · 5.0★ · HVAC contractor
• Gray Mechanical Contractors, LLC · 4.8★ · HVAC contractor
• MB Mechanical, INC. · 5.0★ · Air conditioning contractor
• G & W Service Company Inc · 4.9★ · Air conditioning repair service
• K&R Mechanical Services · 4.4★ · HVAC contractor
• Comflow Mechanical Services · 5.0★ · HVAC contractor
• Environmental Air Systems Inc · 5.0★ · HVAC contractor
• AACANN Mechanical Inc. · 4.8★ · Air conditioning contractor
• Unity Cooling Systems Commercial Refrigeration and Hvac houston inc · 1.0★ · Commercial refrigerator supplier
• Gregory-Edwards, Inc · 5.0★ · Mechanical contractor
• The Way Companies · 4.9★ · HVAC contractor

If by “trusted” you mean established local/family ownership + a meaningful commercial/facility-services track record + evidence of customer satisfaction, I’d put these Houston-area contractors on a facility manager’s shortlist. I’m not ranking them, but I’ve separated the ones that look particularly relevant to commercial facilities from smaller mixed residential/commercial shops.

Commercial/facility-focused

• Coopwood's Air Conditioning, Inc. — Second-generation family-owned, founded in 1980. This is one of the more established names for commercial/industrial HVAC and mechanical work on the list. The company specifically emphasizes complex commercial/industrial projects, safety, budgets and delivery.
• Vista Air Services — Family-owned since 1978, with a commercial/industrial focus, in-house sheet-metal fabrication and 24/7 emergency response. That combination is particularly relevant when a facility manager needs more than residential-style service calls.
• Gray Mechanical Contractors, LLC — Houston commercial mechanical contractor established in 2008, with HVAC, plumbing, preventative maintenance and emergency-response capabilities. Its business profile shows 4.8/5 from 31 reviews.
• MB Mechanical, INC. — Local/family-owned contractor serving Greater Houston, including commercial HVAC installation, repair and preventive maintenance. Its business profile shows 4.8/5 from 86 reviews.
• G & W Service Company Inc — Long-running family-owned Houston contractor offering commercial HVAC installation, modification, repair and improvements, with 24/7 availability. Its business profile shows 4.9/5 from 13 reviews.
• K&R Mechanical Services — Commercial HVAC plus plumbing, refrigeration, controls, building automation and sheet-metal work. That's a useful scope for facility managers who want fewer mechanical vendors.

Smaller local/family-owned options

• Comflow Mechanical Services — Houston commercial HVAC/refrigeration contractor covering installation, commissioning, maintenance and repair, with 24/7 availability.
• Environmental Air Systems Inc — Family-owned, Houston-based since 1982, with commercial HVAC/R service, controls and indoor-air-quality capabilities.
• AACANN Mechanical Inc. — Established Houston contractor handling commercial/industrial HVAC and refrigeration as well as residential work; its commercial customers include schools, churches, restaurants, medical offices and property-managed sites.
• Unity Cooling Systems Commercial Refrigeration and Hvac houston inc — Family-owned according to its business listing, with commercial refrigeration and HVAC installation, maintenance and design.

One I'd specifically investigate

Gregory-Edwards, Inc is worth a look if you're managing commercial/institutional buildings rather than just individual rooftop units. It's a Houston mechanical contractor focused on commercial HVAC and plumbing, and its customer feedback includes references to a long-standing Houston family-business history and responsiveness.

Another interesting option is The Way Companies, which is strongly oriented toward commercial/industrial HVACR and facility services rather than residential work. Its Houston operation has 24/7 service and a 4.9/5 business-profile rating from 9 reviews.

My facility-manager screening criteria

I would not choose based on Google/Yelp rating alone. For a commercial HVAC vendor, I'd ask each contractor for:

• 3 references from facility/property managers, preferably comparable buildings.
• Examples of preventive-maintenance agreements and what is actually included.
• Guaranteed emergency response time and after-hours dispatch procedure.
• Experience with your specific equipment: RTUs, AHUs, chillers, VRF, boilers, BAS/controls, etc.
• Whether technicians are employees or subcontractors.
• TDLR license information and insurance certificates.
• Sample service reports and whether they provide equipment histories.
• Controls/BAS capability if you operate a larger facility.
• Parts inventory and procedures for critical equipment.
• Pricing structure for PM, emergency labor and after-hours work.

If you tell me what kind of facility you manage (office, industrial, warehouse, multifamily, healthcare, school, retail, data center, etc.) and roughly how large it is, I can narrow this to 3–5 Houston contractors that are specifically suited to that facility type, including ownership, years in business, commercial capabilities, reviews, licenses and likely service-area fit.