Fast Affordable Air completed a rooftop Air Conditioning project for a property in the Las Vegas Valley. The pictures show an older roof-mounted system, the replacement HVAC unit, new sheet-metal connections, drainage piping, electrical conduit, and weather sealing around the work area.
This type of central Air Conditioner is called a rooftop package unit. A package unit places most of the Heating and Cooling parts inside one large cabinet. Instead of having one part inside and another part outside, the main equipment sits together on the roof.
Homeowners can learn more about similar projects through Fast Affordable Air’s AC repair services in Las Vegas and Air Conditioning installation services.
Inspecting the Older Rooftop Air Conditioner
The first picture shows the older rooftop AC system. Its cabinet had been exposed to years of strong sunlight, wind, dust, and changing weather. The unit was mounted above the shingle roof on a metal support frame.
The large metal section connected to the side of the Air Conditioner is part of the duct system. A duct is a metal passage that carries air. One duct sends cooled air into the building while another brings warmer indoor air back to the HVAC system.
Before installing replacement equipment, a technician must inspect the stand, roof opening, duct size, electrical supply, drainage path, and surrounding shingles. A new central AC cannot work correctly when it is connected to damaged or poorly sealed ductwork.
Checking the Roof Openings and Drainage Route
Another picture shows PVC piping running across the roof and entering through a sealed roof opening. PVC is the white plastic pipe often used to carry condensation away from an Air Conditioning system.
Condensation is water made when warm, humid air touches the cold evaporator coil inside the AC. It is similar to the water that forms on the outside of a cold drinking glass.
This water must have a clear path away from the equipment. A blocked, broken, or poorly sloped drain can allow water to collect inside the unit or spill onto the roof. During the project, the drainage route was checked so water could move away from the Cooling equipment instead of building up around it.
Inspecting the Condenser Fan Area
The close-up picture of the top fan shows part of the condenser fan assembly. The condenser fan pulls outdoor air through the coil and helps remove heat from the refrigerant.
Refrigerant is the special fluid that moves heat from inside the building to the outdoors. It does not simply make cold air. It collects indoor heat and carries that heat outside.
The fan motor, wire terminals, mounting hardware, and protective grille should be inspected before startup. A loose electrical terminal can create heat and may damage the motor. A fan blade that rubs against the grille can also create noise and reduce airflow.
Setting the Replacement Rooftop Package Unit
The next group of pictures shows the replacement package Air Conditioner positioned on the rooftop support. Proper placement is important because the cabinet must remain level, stable, and correctly lined up with the building’s air openings.
A rooftop HVAC unit is heavy. Its weight must rest on a suitable frame or curb instead of pressing directly against weak roof materials. The support also keeps service panels accessible for future inspections and repairs.
During placement, the supply and return openings must line up with the duct system. A poor match can restrict airflow. Restricted airflow means the blower has to work harder to push air through the building.
Installing the New Sheet-Metal Duct Transition
The bright metal sections beside the replacement unit are custom duct transitions. A duct transition is a shaped piece of sheet metal that joins two air openings that are not exactly the same size or shape.
The transition creates a smooth path between the rooftop central Air Conditioning system and the existing ductwork. It also helps keep the supply air and return air separated.
The joints should be fastened securely and sealed against air leaks. Even a small opening can release cooled air onto the roof instead of sending it into the rooms below. That lost air can lead to longer run times, uneven temperatures, and unnecessary energy use.
Sealing the Ductwork and Roof Area
Several pictures show sealed joints around the ductwork, support frame, and roof penetrations. A roof penetration is any place where a pipe, wire, duct, or support passes through the roof covering.
These areas need careful weatherproofing. Roof-grade sealant and mastic may be used around approved joints. Mastic is a thick sealing material that is brushed or spread over a connection. When it cures, it helps block air and moisture.
Good sealing provides two kinds of protection. It helps keep rainwater from entering the building, and it helps stop extremely hot rooftop air from leaking into the Central Cooling system.
Routing the Electrical Conduit
The flexible metal tube connected to the cabinet protects the electrical wires. This tube is called a conduit or electrical whip. Its job is to shield the wires from sunlight, weather, movement, and accidental damage.
The nearby electrical disconnect allows power to the HVAC unit to be shut off during service. Before startup, the technician should check the supply voltage, wire connections, grounding, breaker size, and disconnect operation.
Correct electrical connections help the compressor, blower motor, and condenser fan start and run safely. Loose wiring can cause overheating, damaged controls, or unexpected system shutdowns.
Securing the Utility Connections
The pictures also show a wrapped utility line routed between the equipment and the roof connection. The exact purpose of this line cannot be confirmed from the photos alone, but any electrical, fuel, control, or service connection must be protected and supported correctly.
Lines should not be left rubbing against sharp sheet-metal edges. They should also have enough room for normal movement without being stretched, pinched, or placed where water can collect.
Completing the Startup Inspection
After the physical installation, a proper startup inspection should include checking airflow, electrical readings, drainage, fan operation, thermostat response, and the temperature of the air entering and leaving the system.
The technician should also listen for vibration and confirm that access panels are secured. Loose panels can make noise and allow outside air to enter the cabinet.
Fast Affordable Air provides rooftop AC, central Air Conditioner, and other HVAC services throughout Las Vegas, Henderson, North Las Vegas, and nearby Clark County communities.
Benefits of the Rooftop HVAC Upgrade
- More dependable Cooling because the replacement unit is securely positioned and properly connected to the duct system.
- Better airflow from a correctly shaped sheet-metal transition with fewer gaps and restrictions.
- Less wasted energy because sealed duct joints help keep cooled air inside the system.
- Improved roof protection through careful sealing around pipes, supports, ducts, and other roof openings.
- Safer electrical operation from protected wiring, secure conduit, and an accessible disconnect.
- Controlled water drainage that moves condensation away from the Air Conditioner and roof surface.
- Easier future service because the equipment panels and utility connections remain accessible.
Actual energy savings depend on the equipment efficiency, system size, duct condition, thermostat settings, building insulation, and daily use. Proper installation helps the replacement Heating and Cooling system perform as designed without losing air through poorly fitted connections.
