At Fast Affordable Air, our licensed HVAC team was recently called out to inspect and repair a rooftop air conditioning unit for a commercial property in Las Vegas, NV. The central cooling system, a Rheem RGEAZR060AJT model running on R-410A refrigerant, was struggling to keep indoor temperatures comfortable. The complaint: weak airflow and poor cooling, even during full operation.
Step 1: Manifold Gauge Readings
We connected our Yellow Jacket manifold gauge to check refrigerant pressures. Here’s what we found:
- Low-side pressure (blue gauge): ~122 psi
- High-side pressure (red gauge): ~305 psi
For systems using R-410A, these readings suggest the system was running within the expected range, though the high side could indicate possible airflow or coil restrictions. These numbers tell us the refrigerant circuit is likely intact, which rules out major leaks or compressor failure.
Step 2: Supply Air Temperature Measurement
We used a digital thermometer to measure the air coming out of the supply vent. The reading was:
46.7°F
This is an excellent temperature for a supply duct, indicating the evaporator coil is cooling well. For context, anything between 45°F and 55°F is usually considered efficient for central air conditioning systems.
Step 3: Amp Draw Test
We also checked the amp draw on the system, and it measured at 15.39 amps using a Fieldpiece SC260 clamp meter. This confirms the compressor and motor are functioning, and there’s no sign of overheating or electrical strain.
Step 4: Capacitor Inspection
We inspected the dual-run capacitor responsible for powering the fan motor and compressor. The unit was a CSC 45+15 µF ±6% at 440V, which was still operating within range. Capacitors can lose charge over time, leading to weak starts or total shutdown. In this case, the part checked out fine, so we left it in place.
Final Checks and Performance
With pressures, temperatures, and electrical components operating within spec, we performed a final rinse on the outdoor coil to remove dust buildup. This helps improve heat exchange and prolongs compressor life.
Why This Matters
- Stable Cooling: A 46.7°F supply air temp means your AC is doing its job, pulling heat and moisture out of the air.
- Efficient Operation: Proper refrigerant pressure and amperage confirm the system isn’t overworking—this keeps electric bills lower.
- Reliable Components: Testing and verifying components like capacitors ensures the system starts up smoothly without strain.
This project is a great example of how regular maintenance and expert diagnostics from Fast Affordable Air can keep your cooling system running efficiently all summer long in Las Vegas, Henderson, and North Las Vegas.
