Rooftop Units & Light-Commercial HVAC for Local Businesses

Keep your business running without interruption. We install, service, and repair rooftop units and light-commercial HVAC systems for offices, retail spaces, restaurants, and warehouses across Macomb and St. Clair Counties.

Dependable HVAC Support for Local Businesses

Downtime costs money — whether it’s an office that’s too hot to work in, a restaurant losing refrigeration, or a retail space losing customers to an uncomfortable storefront. At S. Finzel Mechanical, we specialize in rooftop units (RTUs) and light-commercial systems, keeping your building comfortable and your operations running smoothly.

Whether you need emergency repair on a failing rooftop unit, routine maintenance to avoid unexpected breakdowns, or a full system replacement for an aging building, our technicians understand the demands of commercial equipment and work efficiently to minimize disruption to your business.

Complete Commercial HVAC Care, Start to Finish

From rooftop repairs to full system installs, our licensed technicians keep local businesses comfortable.

Rooftop Unit (RTU) Repair

Fast diagnosis and repair of packaged rooftop units for offices, retail, and restaurants, minimizing downtime for your business.

Commercial System Installation

Properly sized rooftop and split-system installations for new builds, renovations, or aging equipment replacement.

Preventative Maintenance Plans

Scheduled inspections and tune-ups that catch small issues before they become costly breakdowns or code violations.

Emergency Commercial Repair

Priority response for businesses facing no-heat, no-cool, or equipment failure during operating hours.

Signs Your Commercial HVAC Needs Attention

Uneven Temperatures Throughout the Building

Some areas of your space run hot or cold no matter how the thermostat is set.

Rooftop Unit Short Cycling or Won't Start

The RTU turns on and off repeatedly, trips breakers, or fails to start at all.

Rising Utility Bills

Energy costs climbing without a clear change in usage, often a sign of an aging or failing system.

Unusual Noises or Odors from Rooftop Equipment

Grinding, rattling, or burning smells coming from rooftop or mechanical room equipment.

Frequent Repairs or an Aging System

Your unit is calling for repairs more often, or it's approaching the end of its typical 10–15 year lifespan.

Back in Business in Three Simple Steps

Call & schedule

Reach a live local team and book a time that works around your business hours priority response for emergencies.

Inspect & Quote

A licensed technician inspects your rooftop or commercial system and provides clear, up-front pricing before any work begins.

Repair & Restore Operations

We complete the work efficiently, test the system thoroughly, and help you get back to business with minimal disruption.

Common Commercial hvac questions

Can you service rooftop units on occupied commercial buildings?

Yes we routinely work on occupied buildings and coordinate scheduling around your business hours to minimize disruption to customers and staff.

Do you offer emergency service for businesses?

Yes, we prioritize emergency response for businesses facing no-heat, no-cool, or equipment failures, since downtime directly affects your operations.

How often should commercial HVAC systems be serviced?

We recommend at least twice-yearly maintenance for commercial rooftop and light-commercial systems, since they run longer hours and see more wear than residential equipment.

What types of businesses do you work with?

We service offices, retail stores, restaurants, warehouses, and other light-commercial spaces throughout Macomb and St. Clair Counties.

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