In the spectrum of HVAC systems, there is an important appliance called the packaged rooftop heating and cooling unit (or RTU). As the name suggests, RTUs get placed on the roof of single-story retail outlets and small commercial buildings. They provide conditioned air for one concise unit. RTUs look like a large metal box that contains the following components:
  • An expansion device
  • An evaporator
  • A compressor, and
  • An air-cooled condenser

Delving deeper into RTUs

These units typically connect directly to a ductwork system. The system then distributes heated or cooled air throughout the space and returns it to the rooftop unit.
First, the air returns from the indoor space and passes back to the RTU. Also, sometimes, outdoor air gets brought into the unit and gets mixed with the return air. The result is fresh air that flows back inside. Inside the RTU, the air dodges through one or more filters on its way to the heating or cooling coil. Here, the RTU chills that air by running it over the cold refrigerant. Then, the air flows through blowers, leaving it conditioned. It is then ready for delivery into the building.
Note, however, that some units contain small healing elements close to the blowers. Here, the humidity of the air can be further adjusted. In packaged RTUs, there is an insulated device in the unit between the evaporator coils and the condenser coils and compressor. The evaporator coils cool the return air, and the condenser coils and compressor eject the heat into the atmosphere.

Specialised applications

There are some peculiar applications and uses for an RTU. They are popular when fresh air is needed indoors (i.e.. Manufacturing or restaurant spaces). There is no return air brought back from the indoor space. Such packaged rooftop units are 100 per cent dedicated outdoor air units. These require increased insulation, additional parts and higher energy to function properly.

Sales and Service for Rooftop packaged units

A-1 Heating and Air Conditioning specialises in HVAC installations and solutions. If you think you need a new RTU or RTU repair, give us a call. We are here for your regular HVAC maintenance, cleaning and replacement units. We provide outstanding warranties on all our RTUs.