Do you only do commercial refrigeration?

Commercial walk-ins, reach-ins, and rack systems are our focus on the refrigeration side. We do not service residential refrigerators; for those, your appliance dealer is the right call.

How fast can you respond to a down walk-in?

Active maintenance customers typically see a tech within 2 hours, any hour, any day. New customers calling the emergency line usually get one within a few hours during business hours, or that same evening for after-hours calls.

Can you size a new walk-in for our space?

Yes. We run the load calculation, size the equipment, and design the refrigerant lines for new builds and remodels. You get a written scope with permit-ready specs.

Commercial Refrigeration in the Bay Area

Commercial Refrigeration.

A walk-in down at 2am costs you inventory by the minute. Onzone runs 24/7 commercial refrigeration service across the Bay Area for restaurants, grocery, and retail.

Walk-in coolers, reach-in freezers, refrigeration line work, condenser racks. EPA-certified handling on every refrigerant we service. Real human on the emergency line, real tech on the way.

Problems we fix every day.

Walk-in running warm

When box temperatures drift above setpoint, we work the whole circuit: evaporator fans, controls, door gaskets, airflow, refrigerant charge, and compressor operation, until the number holds.

Reach-in temperature swings

Prep tables and display coolers that swing warm mid-shift usually have short cycling, a dirty condenser, a failed thermostat, a blocked drain, or a fan problem. We diagnose on site and fix what we find.

Refrigerant line leaks

We locate the leak, repair the damaged copper, pressure test, evacuate, and recharge with the correct refrigerant, verified by measured superheat or subcooling rather than topping off and hoping.

Compressor trips breaker

Before anyone says replacement, we check electrical load, contactors, capacitors, winding condition, head pressure, and condenser airflow. Sometimes it is the compressor. Often it is not.

Roma Govorko June 2026

Oleg did an excellent job with our HVAC system. He was professional, knowledgeable, and very easy to work with. He arrived on time, carefully diagnosed the issue, and explained the repair options in a clear and honest way. The work was completed efficiently and with great attention to detail. Everything was left clean, and the system is now running perfectly. It's clear that Oleg takes pride in his work and genuinely cares about providing quality service. I highly recommend Oleg to anyone looking for a reliable and experienced HVAC specialist. I would not hesitate to hire him again for future heating and air conditioning needs.

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Mohamed Faisal May 2026

Mr Oleg and his team were excellent in fixing the attic fan at my home at a very reasonable rate. I would highly recommend the team.

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Brandon Wang July 2026

I had an excellent experience with ONzone Heating & Cooling. Oleg was professional, friendly, and very knowledgeable from the moment he arrived. He carefully inspected my air conditioning system, explained exactly what the problem was in a way I could understand, and completed the repair quickly and efficiently. I really appreciated that he took the time to answer all of my questions and never tried to sell me services I didn't need. After the repair, he made sure everything was working perfectly before leaving. My AC is now cooling better than it has in a long time. It's not easy to find a company that is honest, reliable, and truly cares about customer satisfaction, but ONzone Heating & Cooling exceeded my expectations. I will definitely call Oleg again for any future HVAC needs and will gladly recommend ONzone Heating & Cooling to my family, friends, and neighbors. Thank you for the outstanding service!

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Commercial Refrigeration.