How Often Should a Commercial Rooftop Unit Be Serviced? A Guide for Michigan Restaurant and Retail Owners

Why rooftop units fail more often than they should

Packaged rooftop units combine the compressor, condenser, evaporator, blower, and often gas heating in one cabinet on the roof, exposed to everything a Michigan year delivers: summer heat, freezing rain, snow load, and the pollen and cottonwood that clog condenser coils every spring. Inside a restaurant, they also fight kitchen grease that coats coils and filters. That combination of exposure and constant runtime is why most RTU failures trace back to the same handful of causes: dirty coils, clogged filters, worn belts, failing capacitors and contactors, low refrigerant from slow leaks, and controls or economizer dampers that drifted out of adjustment years ago.

None of those are dramatic. Each one raises energy use and strain a little, and left alone for a few seasons they add up to a compressor failure that could have been avoided for a fraction of the cost.

The maintenance schedule that works

For a typical retail or office space, two professional visits a year is the baseline. A spring visit prepares the cooling side: clean the condenser and evaporator coils, check refrigerant charge and pressures, test capacitors, contactors, and the compressor amp draw, inspect and tighten electrical connections, verify the condensate drain is clear, check belts and blower alignment, and confirm the economizer is bringing in outdoor air when it should and not when it should not. A fall visit prepares the heating side: inspect the heat exchanger, burners, igniter, and gas pressure, test the safety controls and limit switches, and check the flue.

Restaurants, gyms, and other high-load spaces are better served quarterly. Kitchen exhaust and make-up air systems put unusual stress on rooftop equipment, and grease-laden air fouls filters and coils quickly. Filter changes should happen every one to three months regardless of the professional schedule, and in a restaurant the shorter end is usually right. A clean filter is the single cheapest thing that protects a compressor.

Between visits, someone on your staff should know where the thermostat is, what a normal temperature looks like, and who to call. Catching a problem on a Tuesday afternoon is a service call. Catching it on a Saturday night is an emergency.

Repair or replace: reading the signs on a rooftop unit

Rooftop units in our climate commonly last 15 to 20 years with consistent maintenance, and closer to 10 to 12 without it. Age is the starting point, and the same logic we apply to a home furnace applies here: a repair on a unit under 10 years old is almost always worth it, and a major repair on a unit past 15 rarely is.

The signals that a unit is nearing the end are familiar. Repeated service calls on the same unit, rising energy costs that do not track with weather or occupancy, a major component failure such as a compressor or heat exchanger, and persistent comfort complaints from staff or customers that repairs do not resolve. When two or more of those show up together, the unit is telling you something.

There are also reasons to replace before failure. Older rooftop units are far less efficient than current equipment, and on a unit that runs most of the day, most days of the year, the energy savings from a modern high-efficiency replacement can be substantial. New units also use R-454B refrigerant rather than R-410A; as R-410A becomes more expensive for servicing older equipment, refrigerant-related repairs on aging units get harder to justify. And a planned replacement in April on your schedule costs less and disrupts less than an emergency replacement in July with a crane rental on a rush basis.

Planning across multiple locations

If you operate several sites, the most valuable thing you can have is an accurate inventory: every rooftop unit, its age, tonnage, refrigerant type, service history, and known issues. Most multi-site operators we start working with do not have this, and it is the first thing we build. With it, you can budget replacements a year or two out instead of reacting, prioritize the units most likely to fail, and negotiate equipment purchases in groups rather than one crisis at a time.

A single mechanical contractor covering all of your Southeast Michigan locations also means consistent standards, one point of contact, and technicians who already know your buildings. When a unit does go down, the call is shorter because we already have the history.

What a good maintenance agreement should include

Look for a written scope that lists the specific checks performed on each visit, not just "tune-up." Look for documentation after every visit with readings, findings, and recommendations, so you have a record and can see trends. Look for priority scheduling for emergency calls, because when your dining room is hot, being first in line matters. And look for a contractor who will tell you when a unit is not worth another repair, even when the repair would be easy money.

That last one is how we operate. We would rather help you plan a replacement on your terms than keep billing you for repairs on equipment we know is finished.