Commercial HVAC repair in San Mateo County
Unit down in your building? Let's fix it.
A commercial repair starts with finding what actually failed: we test the electrical side, the refrigerant circuit, the airflow and the controls, then repair the part at fault. We work on rooftop package units and building systems across San Mateo and Santa Clara counties.
What a commercial repair visit covers
When a building's heating or cooling stops, the job is to find the one thing that failed, not to swap parts until it runs. A visit goes in this order.
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You tell us what the unit is doing
No cooling, no heat, a unit that starts and stops, a noise, a tripped breaker, water where it shouldn't be. Tell us when it started and which part of the building feels it.
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We test before we touch anything
Electrical readings first, with a clamp meter on the wiring and the motors, then refrigerant pressures and temperatures, the coils, the airflow and what the controls are telling the unit to do.
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We repair what failed
A capacitor, a contactor, a motor, a drain, a coil, a leak: the repair goes at the cause. If the answer is a bigger job, we say so and explain the choice.
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We run it and check it
The unit runs through a cycle before we leave, with the readings checked again, so you know it is actually working.
What usually takes a commercial HVAC unit down?
These are the faults we look for first on a unit that has stopped cooling or heating:
- Electrical parts. Failed capacitors and contactors, worn motors and loose or burnt connections stop a fan or compressor from starting.
- Refrigerant leaks. Low refrigerant means a leak somewhere, and topping it up without finding it only buys time.
- Dirty or iced coils and clogged filters. Air can't move or heat can't leave, so the building stays warm or cold.
- Blocked condensate drains. Water backs up, and many units shut themselves off when the pan fills.
- Controls and sensors. A unit can be mechanically fine and still be told to do the wrong thing.
Can you diagnose a rooftop package unit?
Yes. Rooftop package units are the commercial work we have photos of: in July 2026 a technician opened a rooftop unit's panel and read its wiring with a clamp meter, which is how a rooftop diagnosis starts.
The unit holds the cooling, the heating and the fan in one cabinet, so one failed part can take the whole system down. Finding which part is the job.
What should I have ready when I call?
The unit's nameplate if you can read it: the maker, the model and the serial number. Then what the unit is doing, when it started, and whether a breaker has tripped.
Also tell us how we get to the unit, whether that is a roof hatch, a ladder or a locked door, and who can let us in and approve the work.
Tell us what the unit is doing
Call and describe it, or book a visit online.
Is it worth repairing an older commercial unit, or should we replace it?
If the fault is a part, repair usually makes sense. It is worth pricing a replacement when the compressor has failed, when the unit keeps losing refrigerant, or when one repair follows another.
A replacement unit has to meet the state's refrigerant rule, which can change what you are choosing between.
Tell us what it's doing. We'll take it from there.
Call and describe the problem: the noise, the smell, the room that never warms up. Or book a visit online.
