A dependable Air Conditioner is not optional during a Las Vegas summer. For this project, our technician replaced an aging rooftop system with a new Rheem packaged HVAC unit. The completed installation provides central Air Conditioning from one compact cabinet mounted on the roof.
A packaged HVAC unit contains the main heating and cooling parts inside one outdoor cabinet. This differs from a split system, which has separate indoor and outdoor equipment. Packaged units are common on Las Vegas homes because they save space and connect directly to the ductwork below the roof.
Evaluating the Existing Rooftop Air Conditioner
The first photo shows the previous rooftop unit before replacement. When an older AC develops major problems, the technician must consider its age, condition, repair cost, and expected reliability. A small electrical part may justify an Air Conditioning repair. However, replacing the equipment can make more sense when the central AC has extensive wear or needs an expensive major component.
The technician also examines the roof curb. A roof curb is the raised metal base that supports the HVAC cabinet and connects it to the home’s supply and return ducts. The supply duct sends conditioned air into the rooms. The return duct pulls indoor air back to the unit so it can be cooled again.
Removing the Old Cooling Equipment
The electrical power was shut off before the old equipment was disconnected. Rooftop Heating and Cooling systems have high-voltage wiring, so this work must be completed with the proper safety procedures.
The old packaged unit was separated from the electrical connection, duct opening, and roof curb. It could then be lifted away without damaging the surrounding shingles or nearby solar panels. The mounting area was inspected and prepared for the replacement equipment.
Installing the New Rheem Packaged HVAC Unit
The replacement Rheem unit was positioned on a new galvanized metal transition and curb assembly. A transition is a shaped sheet-metal section that allows the openings on the new Air Conditioner to line up with the home’s existing ductwork.
Correct alignment matters. A poorly fitted transition can allow conditioned air to leak into the roof space instead of reaching the rooms. That makes the Central Air Conditioning system run longer and can raise electricity use.
The metal base was secured and sealed around the roof connection. This provides a stable platform while helping keep rainwater and outside air away from the duct openings. The photos show clean metalwork surrounding the bottom of the cabinet and a level installation above the roof.
Electrical Connection and Service Access
The new flexible electrical conduit was routed into the Rheem cabinet and secured. A nearby disconnect allows a technician to turn off power while servicing the equipment. A disconnect is a safety switch located close to the HVAC unit.
Enough working space was also maintained around the service panels and outdoor coil. The outdoor coil is the large finned section visible on the side of the equipment. Air must move freely through these fins so the system can release heat collected from inside the home.
Testing the Central Cooling System
After installation, the system was powered on and tested in Cooling mode. The technician checked operation and measured the air coming from an indoor supply vent with an infrared thermometer. The photo shows a reading of approximately 63.7°F.
This reading confirms that cool air was reaching the room. However, one vent temperature alone does not measure the full performance of an AC system. A technician normally compares the return-air temperature with the supply-air temperature. The difference is called the temperature split. For example, air entering the system at 80°F and leaving at 60°F produces a 20-degree temperature split.
Final testing may also include checking airflow, electrical operation, thermostat response, and drainage. Proper airflow helps the central Air Conditioner cool rooms evenly. It also protects the equipment from problems caused by restricted air movement.
Benefits of the New Rheem System
- More dependable cooling during extreme Clark County temperatures
- Improved indoor comfort when the equipment and airflow are correctly matched to the home
- Quieter operation compared with many worn rooftop systems
- Better service access through clearly arranged exterior panels
- Potential energy savings when replacing an inefficient unit with properly sized modern equipment
- Protected duct connections through a fitted and sealed metal transition
Actual energy use depends on several factors, including equipment efficiency, system size, duct leakage, insulation, thermostat settings, and daily weather. Even a high-quality Heating and Cooling unit can waste power if it is oversized or installed incorrectly.
Why Rooftop Installation Details Matter
Las Vegas rooftops face strong sunlight, high temperatures, dust, and sudden desert rain. The equipment must sit securely, while the roof connection needs proper flashing and sealing. The outdoor coil must also remain clear of walls, solar panels, and other objects that could block airflow.
Fast Affordable Air provides licensed HVAC services in Las Vegas and surrounding Clark County communities. Homeowners experiencing a sudden system failure can also review information about air conditioning maintenance and service. When replacement becomes necessary, comparing system design and efficiency is just as important as comparing brand names, as explained in this guide to choosing an AC system in 2026.
Project Summary
This project included removing an aging rooftop packaged unit, preparing the mounting area, installing a Rheem packaged HVAC system on a fitted metal transition, reconnecting the electrical supply, sealing the roof and duct connections, and testing indoor Cooling performance. The finished installation produced approximately 63.7°F air at the measured supply vent.