In Utah’s commercial real estate market, rooftop package units (RTUs) are everywhere—and they are often the most underestimated risk factors in many transactions. These all-in-one HVAC systems provide heating, cooling, and air distribution for most commercial buildings, and when they fail, the impact is immediate and costly. Tenants complain, operations are disrupted, and owners face unexpected capital expenses. From a commercial property inspection perspective, evaluating an RTU isn’t just about turning up the thermostat to feel warm or cool air. It’s about verifying that both the furnace and air-conditioning sections operate safely, efficiently, and within design limits. For buyers, investors, and agents involved in commercial property inspections in Utah, a proper RTU assessment uncovers deferred maintenance, hidden safety risks, performance issues, and realistic short-term capital needs.
Combustion Safety and Heat Exchanger Integrity
Every thorough furnace assessment begins with combustion safety. The furnace must burn cleanly and consistently. During inspection, flame patterns are checked to ensure flames are stable, properly shaped, and not encroaching on the heat exchanger or burners. Flame infringement is a significant warning sign—it accelerates heat exchanger failure and increases the risk of carbon monoxide (CO). CO levels are measured at the exhaust flue and should be effectively zero; any detectable level warrants further investigation. The heat exchanger is visually inspected for rust, cracks, or leaks, as once it fails, replacement is usually the only option. Limit switches are verified to be intact and not bypassed, and thermocouples (when applicable) are checked to confirm proper flame detection. These steps establish the baseline for determining whether a rooftop furnace is safe to operate.
Flame Sensors, Ignition, and Controls Testing
Controls, ignition components, and flame detection are often overlooked during superficial inspections. A dirty or failing flame sensor can cause nuisance shutdowns and erratic heating cycles. During evaluation, the flame sensor’s microamp output is tested before and after cleaning. In a properly functioning system, readings should stay within the acceptable “good” range both times, confirming stable flame detection. The sensor is then cleaned to remove oxidation and carbon buildup. Ignitor performance is assessed by measuring amperage draw; a typical healthy reading may be around 0.53 amps, depending on manufacturer guidelines. Weak ignitors and marginal flame sensors often pass casual inspections but fail during the coldest Utah mornings, when tenants need heat most.
Motors, Airflow, and Gas Pressure Checks
Next is the mechanical aspect of furnace performance: motors, airflow, and gas delivery. The inducer motor’s amperage draw is checked—usually around 0.37 amps under normal conditions—to ensure it isn’t overloaded or close to failing. The blower motor’s amperage is also measured; readings such as 3.29 amps indicate whether it operates within design limits. Excessive draw suggests bearing wear, airflow restrictions, dirty components, or failing windings. Gas pressure is checked to confirm proper delivery to the burners; readings above 50 (per system design) indicate the furnace isn’t starved for fuel. Pressure switches are tested to verify they operate correctly, ensuring the draft system properly proves combustion airflow before ignition. These checks distinguish accurate diagnostics from checkbox inspections.
Cooling Performance, Refrigeration Circuit, and Electrical Load
Assessing the air-conditioning section of an RTU is just as critical as evaluating the furnace. The condenser and evaporator coils are checked for dirt buildup, bent fins, and corrosion, all of which reduce heat transfer efficiency and increase operating costs. Refrigerant line insulation is inspected for deterioration or missing parts that can cause capacity loss and strain on the compressor. The compressor’s amperage draw is measured to determine whether it operates within the manufacturer’s limits or shows signs of overloading or wear. Condenser fan motors are also examined for proper operation and amperage draw, as weak or failed fans can quickly lead to high head pressure and compressor failure. Supply and return air temperatures are measured to ensure the system provides an appropriate temperature split and verifies that cooling capacity is being delivered to the building.
Bringing It All Together
A proper rooftop package unit inspection goes beyond simply confirming that a unit turns on and blows warm or cool air. It involves a data-driven evaluation of combustion safety, heat exchanger condition, flame sensing and ignition reliability, motor and airflow performance, gas delivery, refrigeration circuit health, electrical load, and cooling capacity. These findings help identify deferred maintenance, hidden safety hazards, performance issues, and realistic short-term repair risks that basic inspections often miss. For buyers, investors, and agents involved in commercial property inspections in Utah, this level of analysis provides a solid, defendable snapshot of remaining service life and actual capital exposure. Rooftop units do not fail gradually or inexpensively—they fail suddenly, disrupt tenants, and strain budgets. That is why a thorough RTU inspection doesn’t guess; it measures.
Utah Commercial Inspections offers commercial property inspection services in Salt Lake City and the greater Wasatch Front, covering areas from Ogden to Spanish Fork and Heber to Tooele. Contact us to schedule an inspection.