Commercial HVAC & refrigeration in Orange County.

What commercial-only actually changes

Plenty of HVAC companies list commercial work on their website. Most of them are residential shops that will take a rooftop unit if the phone rings. Davinci Mechanical is the commercial and union division of Scottish Tom's Heating & Air, and it was set up so that commercial work is the only work. That decision shows up in small, practical ways that a facility manager feels within the first service call.

• Trucks are stocked for commercial equipment. Contactors, capacitors, belts, pressure switches, ignition modules, evaporator fan motors and defrost components for walk-ins, and the gauges and leak detection tools that commercial refrigerants require. A residential truck carries none of that in quantity.
• Technicians read commercial controls. Economizer logic, demand control ventilation, staging on multi-compressor RTUs, defrost timers and pressure controls on refrigeration, and the building automation front end that ties it together. Our building controls and automation service covers the front end and everything behind it.
• Scheduling assumes a business is running. Kitchens cannot lose a walk-in during service, tenants cannot lose cooling at 2 p.m. in August, and schools need the work done in a summer window. Night and early-morning work, phased shutdowns and coordination with your property manager are the normal case, not an exception.
• Paperwork is built for the people who will ask for it. Health inspectors want temperature logs. Property owners want capital planning data. Public agencies want certified payroll and closeout packages. All of it is written down, photographed and stored in the DaVinci Portal.
• The commercial code environment is the only one we track. Title 24 mechanical requirements, refrigerant management rules in California, DIR registration and prevailing-wage obligations, and the permit practices of Orange County cities. Residential work has none of this, and a shop that mostly does houses tends to learn commercial compliance on your project.

The upshot is simple. If you manage a restaurant, grocery store, clinic, school, office building, warehouse or hotel, you are not the odd job on the schedule. You are the schedule.

The equipment we live on

Commercial mechanical systems in Southern California fall into a fairly consistent set of categories, and each category has its own failure patterns, parts supply and compliance exposure. These are the systems Davinci Mechanical services every week.

Each of these pages goes deeper on how the equipment is diagnosed, what maintenance it actually needs, and when replacement makes more sense than another repair. The resource guides cover the engineering side in more detail for people who want it.

How a service call runs, from diagnosis to documentation

A commercial service call has a shape to it. Knowing that shape in advance makes it easier to judge whether you are getting real diagnostic work or a technician guessing with your parts budget.

1. Intake. You describe the symptom, the equipment, the site access rules and the hours that work. If the asset already has a QR tag from a previous visit, the technician reads its history before arriving, so they already know what was replaced last time and what readings were recorded.
2. Verify the complaint. The first thing on site is confirming the symptom independently: supply and return temperatures, box temperature on a cooler, hot water delivery temperature, static pressure on an air handler. Many "no cooling" calls are really airflow problems, and many "compressor failed" calls are really a bad contactor or a tripped high-pressure switch with an underlying cause.
3. Work the system, not the part. Electrical readings on every component in the circuit, refrigerant pressures and temperatures converted to superheat and subcooling, airflow across coils, control signals from the thermostat or BAS. The goal is to identify why the failed part failed. A compressor rarely dies on its own.
4. Explain findings before repairs. You get the root cause, the repair options, and the trade-offs in plain language. Where a repair would be throwing money at equipment near end of life, you hear that too, with the data that supports it. Our second opinion diagnostic exists for exactly this moment when another contractor has quoted a major component.
5. Repair and verify. After the repair, the same readings are taken again to prove the fix. A unit that is "running" is not the standard; a unit running within manufacturer specifications is.
6. Document. Readings before and after, photos of the failed component and the completed repair, model and serial numbers, refrigerant added and recovered, and recommendations for future work all go into the asset record in the DaVinci Portal. Your team can pull it up by scanning the tag on the unit.

Who this is for, and who it is not for

Not every business is a good fit for a union commercial contractor, and it is better to say so plainly than to waste a procurement cycle finding out.

A strong fit

• Restaurants and commercial kitchens where refrigeration, ice and hot water are the business, not a convenience. See restaurants.
• Grocery, convenience and retail operators with display cases, walk-ins and sales-floor comfort tied to revenue. See grocery and retail.
• Medical, dental and veterinary practices with medication refrigeration, exam-room comfort and compliance documentation needs. See veterinary and clinics and medical offices.
• School districts, community colleges and public agencies whose projects require DIR registration, prevailing wage, certified payroll and often a project labor agreement. See schools and public works.
• Property managers and owners responsible for multiple buildings who want one documented program and one point of accountability. See property management.
• Warehouses, distribution centers and light industrial facilities with large rooftop fleets, make-up air and sometimes process cooling. See warehouses.
• Hotels, senior living, hospitals and other 24-hour facilities where downtime has consequences beyond discomfort. See the full sector list.

Probably not a fit

• Any residential work. Houses, condos and apartments with individual systems go to Scottish Tom's Heating & Air, not to this division.
• Owners shopping for the lowest number to get a unit running again today, with no interest in why it failed. That approach has its place, but it is not how this company works, and the documentation and diagnostic time that make our work valuable will look like overhead to someone who only wants the cheapest fix.
• Jobs where the specification is "just swap the part the other guy said is bad." We will test the diagnosis first, and sometimes the answer is that the part is fine.

Orange County home base, Southern California footprint

Davinci Mechanical is based in Orange County, and that is where day-to-day service, maintenance programs and emergency response are concentrated. The coastal cities from Seal Beach down through Huntington Beach, Newport Beach, Laguna Beach and Dana Point share salt-air corrosion problems on rooftop equipment. The inland cities along the 5, 55, 57 and 91 corridors, including Anaheim, Santa Ana, Orange, Irvine, Fullerton and Garden Grove, run hotter in late summer and carry some of the densest concentrations of restaurants, retail centers, medical offices and industrial parks in the county. South County cities such as Mission Viejo, Lake Forest, Rancho Santa Margarita and San Juan Capistrano add newer tilt-up office and flex space with large RTU fleets. Each city has its own page under service areas, with notes on the property types and climate exposure that shape maintenance there, and the Orange County region page ties it together.

Beyond Orange County, the company takes on larger commercial, institutional and bid-level work across Southern California: Los Angeles County, the Inland Empire, San Diego County and Ventura County. This is project and contract work, not a promise of a service truck around the corner. There are no local offices or yards outside Orange County, and we say so because a facility manager deciding on an emergency service vendor for a site in Riverside or Oxnard deserves an honest answer about response geography. For a multi-site maintenance program, a central plant project, a school district replacement package or a prevailing-wage contract in those regions, the distance is routine.

For bids on larger projects, the company also quotes nationwide on a project-by-project basis. The nationwide bidding guide explains how that works and what a general contractor or owner should expect from an out-of-area mechanical bidder.

Institutional and bid work

Public agencies and institutions buy mechanical work differently from private owners. There are formal solicitations, bid bonds, prequalification questionnaires, DIR contractor registration, prevailing-wage determinations, certified payroll, apprenticeship ratios and, on many larger projects in Southern California, a project labor agreement. A contractor who has never run that process will learn it on your project, and the learning usually shows up as late paperwork, payroll disputes or a labor compliance audit finding.

As the union division of Scottish Tom's, Davinci Mechanical is built for that environment. UA Local 250 labor comes with the training, certifications and apprenticeship structure that PLAs and public specifications assume. Certified payroll and prevailing-wage compliance are standard practice rather than a special request. The sectors pages describe how mechanical work differs across K-12 districts, colleges, hospitals, city and county buildings, courts, libraries, airports, water utilities and other institutional owners. The bid work pages cover specific public agencies across the five Southern California regions, and the bid projects page explains how to send a solicitation and what a complete bid package from us includes.

• Equipment replacement packages: RTU fleets, split systems, VRF, boilers, water heaters, chillers and cooling towers, with crane logistics, curb adapters, Title 24 compliance and permit handling. See commercial RTU replacement.
• Mechanical scopes on tenant improvements, modernizations and additions, working under a general contractor or directly with the owner.
• On-call and job-order style maintenance and repair agreements for agencies that want a prequalified contractor ready for task orders.
• Multi-year preventive maintenance contracts across a portfolio of public buildings, with documentation that holds up to a labor compliance or facilities audit.

Two guides go deeper for procurement staff: the California prevailing wage guide for HVAC contractors and the public agency and school HVAC procurement guide.

The DaVinci Portal and why documentation is part of the service

Most commercial service records live in a filing cabinet at the contractor's office, in a technician's memory, or in a stack of invoices that describe the work in two lines. When the technician changes or the contractor changes, the history is gone, and every new problem is diagnosed as if the unit had never been touched.

The DaVinci Portal fixes that by attaching a QR-coded record to every piece of equipment we service. Scan the tag on the unit and you see the model and serial, every visit, the readings taken at each visit, photos of the work, refrigerant handled, parts replaced and the technician's recommendations. It is included with service; there is no separate software fee or add-on tier for it.

• For facility managers: answers at the unit, on a phone, without calling anyone. Trend lines on amperage, pressures and temperatures that show a unit degrading before it fails.
• For owners and asset managers: real data for capital planning. Which units have had three compressors, which are near end of life, which are performing fine and should not be replaced yet.
• For auditors and inspectors: refrigerant records, temperature logs and dated photo evidence that match the paperwork, exportable when someone asks.
• For the next technician: the baseline readings and prior findings that turn an intermittent problem into a solvable one.

Maintenance programs that are actually maintenance

A preventive maintenance visit that consists of a filter change and a glance at the thermostat is not preventive maintenance. It is a billing event. Real PM means coils cleaned so condensing temperatures stay where they belong, belts and bearings checked before they fail in July, electrical connections tightened and components tested under load, refrigerant charge verified with superheat and subcooling rather than a gauge glance, drains cleared, economizers and sensors proven to work, and refrigeration defrost cycles and door hardware inspected before the box starts icing.

Davinci Mechanical offers quarterly, bi-annual and annual programs built around the equipment on site rather than a generic checklist. Quarterly suits restaurants, grocery and anyone whose refrigeration or kitchen ventilation is the business. Bi-annual fits offices, retail and medical with seasonal cooling and heating changeover. Annual works for lightly loaded buildings or as a baseline for a portfolio. Each Orange County city has its own maintenance program page with notes on the local property mix, and the preventive maintenance program guide explains what a credible PM scope should include so you can compare any contractor's proposal against it.

How to engage

There are four normal ways to start working with Davinci Mechanical, depending on where you are.

1. Something is down right now. Call (714) 594-9194 or use the contact form. Have the equipment type, location on the property and site access details ready. For Orange County sites, this is the fastest path.
2. You have a quote in hand and want it checked. Book a second opinion diagnostic. We test the system independently and tell you whether the proposed repair or replacement is justified by the readings.
3. You want a maintenance program. Start with the plans page, then request a site survey. The survey produces an asset inventory with QR tags, condition notes on every unit, and a program scope matched to what is actually on your roof and in your kitchen.
4. You have a project or solicitation. Send the drawings, specifications or bid documents through the bid projects page. Public agencies and general contractors can also start from the relevant agency page or sector page.

If you are still comparing contractors, the how to choose a commercial HVAC contractor guide lays out the questions worth asking any bidder, including us. The about page covers the relationship to Scottish Tom's, the union labor model and the licensing posture in more detail.