TL;DR: Most commercial rooftop units across Southeast Michigan have just endured months of sub-zero temperatures, heavy snow loads, and freeze-thaw cycles that push heat exchangers and economizers hard. If your unit is 12 or more years old and has had two or more service calls this winter, late February is the time to get a professional assessment before the cooling season hits and technician schedules fill up. Call Samco FM at (734) 838-6300 to book your RTU evaluation now.
Why Late February Is the Right Time to Assess Your RTU in Michigan
February sits at an ideal crossroads for commercial building owners across Wayne, Oakland, Macomb, and Washtenaw counties. Your rooftop units have just finished peak winter heating load, which means any underlying problems are now visible in your service records and energy bills. At the same time, HVAC contractor schedules are still open before the spring booking rush hits in late March.
Once April arrives and temperatures start swinging between 30 and 60 degrees, every commercial property owner in Metro Detroit scrambles for the same pool of technicians. Units that could have been replaced or tuned in February turn into emergency calls during the first heat wave. That emergency call can cost two to three times more than a planned replacement, and it hits at the worst possible time for your operations.
Michigan’s climate makes this timing more critical than it is in warmer states. Southeast Michigan building owners deal with conditions that simply don’t exist in Tennessee or Arizona: multi-week stretches below zero, repeated freeze-thaw cycles, ice dams on equipment curbs, and snow loads that stress electrical components and drain pans all winter long. The wear your unit has absorbed since November needs to be evaluated before you flip the cooling switch in April.
The Repair vs. Replace Decision: What the Numbers Say
The most common mistake building owners make is fixing the same unit over and over because each individual repair feels cheaper than replacement. The math, however, tells a different story once you run the numbers.
A widely used industry rule of thumb: multiply your RTU’s age by the cost of the repair you’re considering. If that number exceeds $5,000, replacement is typically more cost-effective than repair. A unit that is 15 years old facing a $400 repair clears that threshold easily. An 18-year-old unit facing a $350 repair? Replacement almost always wins on a full cost analysis.
Key figures Michigan building owners should know:
- Average RTU lifespan: 15 to 20 years under normal conditions. After year 15, breakdown frequency increases sharply and parts become harder to source.
- Replacement cost: High-efficiency RTU replacement runs $10,000 to $20,000 installed for most commercial applications. A modern unit can cut HVAC energy consumption by 30 to 40 percent compared to an aging unit running at degraded efficiency.
- R-22 refrigerant exposure: Units manufactured before 2010 likely use R-22, which is no longer produced domestically and now trades at $100 or more per pound. A refrigerant leak on an older unit can turn a manageable repair into a serious budget problem.
- Compressor replacement cost: Commercial compressors run $1,500 to $3,000 in parts alone. On a unit over 12 years old, replacing the compressor often costs more than the remaining useful value of the unit.
Repair is not always the wrong answer. A unit that is 8 years old with a compressor failure and an otherwise clean service history might be worth fixing. The decision turns on age, repair cost, refrigerant type, efficiency rating, and how critical the unit is to your operations. What matters is making that decision deliberately, not reactively during a summer breakdown.
The Michigan Angle: What Your RTU Goes Through Every Winter
Michigan’s climate puts commercial rooftop units through conditions that accelerate wear in specific ways. Building owners in Livonia, Dearborn, Warren, Troy, and Detroit need to understand which components take the most abuse in a Great Lakes winter, because those are the components most likely to fail in spring.
Heat exchangers face sustained stress during extended cold stretches. Michigan regularly sees week-long periods below 10 degrees Fahrenheit, pushing heat exchangers harder and longer than manufacturers typically model for warmer-climate installations. Cracks and micro-fractures in heat exchangers are not a minor issue: they allow carbon monoxide to enter the air stream and put building occupants at risk.
Economizer dampers are exposed to ice and moisture throughout winter. Economizer failures are among the most common RTU problems in Michigan after the cold season. A stuck-open economizer can spike heating costs by 50 percent or more. A stuck-closed economizer cuts your ventilation, degrades air quality, and violates ASHRAE standards for occupied spaces.
Condensate drain pans and lines freeze repeatedly through the season. Repeated freezing cracks drain pans and blocks lines, leading to water damage inside the unit and eventually inside the building itself.
Electrical connections and contactors corrode faster in the presence of winter moisture and road salt particulates carried by wind across Southeast Michigan. Loose or corroded connections discovered after winter are both an efficiency problem and a fire risk.
7 Warning Signs Your Commercial RTU Needs Attention This Spring
If your unit shows any of these signs, schedule an assessment now rather than waiting for a failure during the spring rush:
- Two or more service calls this winter. Repeat repairs are a pattern, not bad luck. If a technician has been to your roof more than once since November, the unit is telling you something about its remaining useful life.
- Unit age over 15 years. After 15 years, mechanical failures become more frequent and parts harder to source. This is the threshold where replacement math usually starts to favor new equipment, especially in Michigan’s climate.
- R-22 refrigerant. If your unit uses R-22 and you have any refrigerant leak, replacement is almost always more economical than paying current R-22 market pricing for a recharge on aging equipment.
- Rising energy bills without a usage change. An RTU losing efficiency shows up in your gas and electric bills before it shows up as a complete failure. A 15 to 20 percent increase in heating costs with no operational change is a warning worth investigating.
- Unusual noise from the rooftop. Banging, grinding, squealing, or rattling that wasn’t there last spring can point to failing compressors, loose heat exchanger baffles, worn motor bearings, or other internal damage caused by winter stress.
- Uneven temperature distribution in your space. Hot or cold spots that your thermostat can’t correct often indicate a failing economizer, low refrigerant charge, or duct system issues tied to RTU performance decline. This is also a sign occupant comfort is already affected.
- Visible damage after winter. Bent fin coils, cracked drain pans, damaged cabinet panels, or corroded electrical connections are all visible signs of winter wear. These issues are easier to find in late February and all get worse once the cooling season begins.
Any single sign may not require replacement on its own. But two or more, especially combined with unit age above 12 to 15 years, shifts the repair-versus-replace equation significantly toward new equipment installed before April.
How Samco FM Handles RTU Assessments Across Southeast Michigan
Samco Facilities Maintenance has served commercial and industrial buildings across Southeast Michigan since 1997. Our team includes 25-plus EPA 608 Universal-certified technicians working across Wayne, Oakland, Macomb, and Washtenaw counties. We hold NATE certification, an A+ BBB rating, and 4.9 stars across 255-plus Google reviews from commercial clients throughout the metro.
Our RTU assessment process is not a sales call. We document the unit’s condition, pull any available service history, measure refrigerant charge and operating pressures, inspect the heat exchanger for cracks, test economizer operation, check electrical connections and contactors, and deliver a written recommendation with repair and replacement costs side by side. You get the information to make the right call for your budget and timeline, not a one-size-fits-all answer.
We serve commercial properties in Detroit, Livonia, and throughout Metro Detroit including Dearborn, Ann Arbor, Warren, Troy, Southfield, Sterling Heights, Canton, Novi, Royal Oak, Farmington Hills, and all surrounding communities. For planned replacements, we can schedule work during low-demand windows in February and March, before spring booking pushes lead times out four to six weeks. For buildings with multiple rooftop units, we can prioritize the units most at risk so your capital budget goes where it matters most.
Reach us at (734) 838-6300 or service@samcofm.com. We offer 24/7 emergency service with 15-minute dispatch for commercial clients.
Frequently Asked Questions
How long do commercial rooftop HVAC units last?
Commercial RTUs typically last 15 to 20 years under normal conditions. Units in Michigan tend to age faster due to freeze-thaw stress, snow loads, and extended sub-zero heating cycles. After year 15, expect more frequent breakdowns and higher repair costs regardless of brand or original quality of installation.
When should I repair vs. replace my commercial rooftop unit?
A common industry rule: multiply the unit’s age by the cost of the repair. If that number exceeds $5,000, replacement is generally more cost-effective. Also weigh the refrigerant type, efficiency rating, and number of service calls in the past two seasons. A written assessment from a NATE-certified technician gives you the data to decide with confidence.
How much does it cost to replace a commercial rooftop unit in Michigan?
Commercial RTU replacement in Michigan typically runs $10,000 to $20,000 installed, depending on unit tonnage, brand, and roof access. High-efficiency replacement units can reduce HVAC energy consumption by 30 to 40 percent compared to aging equipment, which offsets the upfront cost over three to five years for most commercial buildings in the Detroit metro area.
How often should commercial rooftop units be serviced in Michigan?
Michigan commercial RTUs should be serviced at minimum twice per year: a full heating inspection in fall before the cold season and a cooling inspection in late winter or early spring before summer load begins. Buildings with heavy occupancy, restaurant exhaust, or manufacturing operations may need quarterly service. A preventive maintenance contract from Samco FM locks in priority scheduling and consistent pricing year-round.
What are the signs my commercial RTU is failing?
Key failure indicators include: two or more service calls in a single season, unusual noise from the rooftop, uneven temperatures across your building, rising energy bills without increased usage, visible corrosion or physical damage, and any refrigerant leak on a unit over 12 years old. Multiple signs together mean the unit is near the end of its useful life and replacement planning should start now.
Ready to Schedule Your RTU Assessment?
Late February is the best window to act on your commercial rooftop units. Technician availability is good, replacement lead times are short, and you have time to plan before spring cooling demand hits in April. Waiting until May means competing for contractor time with every other commercial building owner in Southeast Michigan who let winter pass without an inspection.
Samco Facilities Maintenance is ready to assess, repair, or replace your commercial RTUs across the Detroit metro. Contact us online at samcofm.com/contact or call (734) 838-6300. Ask about our commercial HVAC services and our spring PM scheduling for buildings with multiple units.
